[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2002.08.10"]
[Round "9"]
[White "Mazajchik, Tim"]
[Black "Koekoek, Arjen"]
[Result "1-0"]
[ECO "B21"]
[PlyCount "57"]
[EventDate "2002.08.05"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2005"]
[Source "ChessBase"]
[SourceDate "2004.11.15"]
[SourceVersion "1"]
[SourceVersionDate "2004.11.15"]
[SourceQuality "1"]

1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 Nc6 5. Nf3 e6 6. Bc4 Qc7 7. 0-0 Nf6 8. Nb5 Qb8 9. e5 Nxe5 10. Bf4 d6 11. Re1 Nxc4 12. Qa4 Bd7 13. Qxc4 Bxb5 14. Qxb5+ Nd7 15. Ng5 Be7 16. Nxe6 fxe6 17. Rxe6 0-0 18. Rxe7 Rxf4 19. Qxd7 Qf8 20. f3 Rf7 21. Rae1 Rxe7 22. Rxe7 Rd8 23. Rxg7+ Qxg7 24. Qxd8+ Qf8 25. Qxf8+ Kxf8 26. Kf2 Ke7 27. Ke3 d5 28. g4 Ke6 29. Kd4 1-0

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2002.08.09"]
[Round "7"]
[White "Greeuw, Sietske"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B32"]
[PlyCount "85"]
[EventDate "2002.08.05"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2005"]
[Source "ChessBase"]
[SourceDate "2004.11.15"]
[SourceVersion "1"]
[SourceVersionDate "2004.11.15"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nb5 a6 6. Nd6+ Bxd6 7. Qxd6 Qf6 8. Qd2 Qg6 9. Nc3 Nge7 10. h4 d6 11. h5 Qf6 12. h6 Nd4 13. Bd3 Be6 14. Qe3 Qg6 15. Qg5 Qxg5 16. Bxg5 Rg8 17. Rh2 f6 18. Be3 gxh6 19. Bxd4 exd4 20. Ne2 Nc6 21. Nf4 Bf7 22. Rxh6 Bg6 23. Nd5 Kf7 24. Rh4 Rae8 25. Nc7 Re5 26. Bc4+ Kg7 27. Bxg8 Kxg8 28. f3 f5 29. Nd5 Kg7 30. Kd2 fxe4 31. fxe4 Bxe4 32. Nf4 d5 33. Rg4+ Kf7 34. Nd3 Rf5 35. Re1 b6 36. a3 Na5 37. b3 Nc6 38. Rf4 Bxd3 39. Rxf5+ Bxf5 40. Rf1 Ke6 41. Rxf5 Kxf5 42. Ke2 Ke4 43. g4 0-1

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2002.08.09"]
[Round "8"]
[White "Koekoek, Arjen"]
[Black "Koffeman, Timotheus"]
[Result "1-0"]
[ECO "B07"]
[PlyCount "69"]
[EventDate "2002.08.05"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2005"]
[Source "ChessBase"]
[SourceDate "2004.11.15"]
[SourceVersion "1"]
[SourceVersionDate "2004.11.15"]
[SourceQuality "1"]

1. e4 d6 2. d4 Nf6 3. Nc3 g6 4. Bg5 Bg7 5. Bc4 0-0 6. f3 c6 7. Nge2 Qc7 8. a4 e5 9. d5 Nbd7 10. Qd2 Nb6 11. Bb3 a5 12. Rd1 Ne8 13. 0-0 Kh8 14. f4 f6 15. Bh4 exf4 16. Nd4 g5 17. Bf2 f5 18. Ne6 Bxe6 19. dxe6 Nc8 20. h4 h6 21. hxg5 hxg5 22. Qd3 Ne7 23. Qh3+ Kg8 24. Qh5 fxe4 25. Nxe4 Nf6 26. Nxf6+ Bxf6 27. Bd4 Kg7 28. Qxg5+ Ng6 29. Rxf4 Bxd4+ 30. Rdxd4 d5 31. Rh4 Rh8 32. Rhg4 Rh6 33. Rdf4 Qb6+ 34. Kf1 Rh1+ 35. Ke2 1-0

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2002.08.08"]
[Round "6"]
[White "Koekoek, Arjen"]
[Black "Van Elteren, Jesse"]
[Result "0-1"]
[ECO "B33"]
[PlyCount "30"]
[EventDate "2002.08.05"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2005"]
[Source "ChessBase"]
[SourceDate "2004.11.15"]
[SourceVersion "1"]
[SourceVersionDate "2004.11.15"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 e5 6. Nf3 Bb4 7. Bc4 0-0 8. Bd5 d6 9. Bd2 Bg4 10. a3 Ba5 11. h3 Bh5 12. g4 Bg6 13. Qe2 Nd4 14. Nxd4 exd4 15. Nb5 Nxd5 0-1

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2002.08.07"]
[Round "4"]
[White "Koekoek, Arjen"]
[Black "Van der Molen, Jarich"]
[Result "1-0"]
[ECO "B72"]
[PlyCount "99"]
[EventDate "2002.08.05"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2005"]
[Source "ChessBase"]
[SourceDate "2004.11.15"]
[SourceVersion "1"]
[SourceVersionDate "2004.11.15"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 g6 5. Nc3 Bg7 6. Be3 Nf6 7. Be2 0-0 8. 0-0 a6 9. h3 b5 10. a3 Bb7 11. Bf3 Qd7 12. Nd5 Qd8 13. a4 b4 14. a5 Nbd7 15. Qd2 Ne5 16. Nxf6+ Bxf6 17. Qxb4 Rb8 18. Qa4 Qc8 19. c3 Nxf3+ 20. Nxf3 Bc6 21. Qc2 Qb7 22. Bb6 Bxe4 23. Qe2 Bxf3 24. Qxf3 Qxf3 25. gxf3 Rfc8 26. Ra4 d5 27. Rc1 e6 28. Rc2 Be7 29. c4 Bc5 30. cxd5 Bxb6 31. Rxc8+ Rxc8 32. axb6 exd5 33. Rxa6 Kg7 34. Kf1 Kh6 35. b7 Rb8 36. Rb6 Kg5 37. Ke2 Kf4 38. Rb4+ Ke5 39. Kd3 g5 40. Rb6 f6 41. Ke3 h5 42. Kd3 f5 43. Ke3 h4 44. Rb5 g4 45. fxg4 fxg4 46. hxg4 Kd6 47. f4 d4+ 48. Kxd4 Kc6 49. Rh5 Rxb7 50. Kc3 1-0

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2002.08.07"]
[Round "5"]
[White "Verheijen, Lennart"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "A88"]
[PlyCount "46"]
[EventDate "2002.08.05"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2005"]
[Source "ChessBase"]
[SourceDate "2004.11.15"]
[SourceVersion "1"]
[SourceVersionDate "2004.11.15"]
[SourceQuality "1"]

1. d4 f5 2. c4 g6 3. g3 Bg7 4. Bg2 Nf6 5. Nc3 c6 6. Nf3 0-0 7. 0-0 d6 8. Bg5 Nbd7 9. Qc2 e5 10. e4 fxe4 11. Nxe4 Qc7 12. Rfe1 exd4 13. Nxd4 Ne5 14. Rad1 Nxe4 15. Bxe4 Qf7 16. Bf4 Bh3 17. Bxe5 Bxe5 18. f4 Bg7 19. Nb5 d5 20. Rxd5 cxb5 21. Rxb5 Rae8 22. Rxb7 Qxb7 23. Bxb7 Bd4+ 0-1

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2002.08.06"]
[Round "3"]
[White "Koekoek, Arjen"]
[Black "Brinks, Jan Willem"]
[Result "0-1"]
[ECO "C01"]
[PlyCount "68"]
[EventDate "2002.08.05"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2005"]
[Source "ChessBase"]
[SourceDate "2004.11.15"]
[SourceVersion "1"]
[SourceVersionDate "2004.11.15"]
[SourceQuality "1"]

1. e4 e6 2. d4 d5 3. exd5 exd5 4. Bd3 Bd6 5. Nf3 Nf6 6. 0-0 0-0 7. c4 dxc4 8. Bxc4 Bg4 9. Be3 Nc6 10. Be2 Re8 11. Nc3 Qd7 12. Qd2 Rad8 13. Rfd1 a6 14. Rac1 Qf5 15. Ne1 Bxe2 16. Nxe2 Ne4 17. Qc2 Nb4 18. Qb3 Nd5 19. Nf3 Nxe3 20. fxe3 Re6 21. Qxb7 Rg6 22. Rf1 Qg4 23. Ng3 Nxg3 24. hxg3 Qxg3 25. Rf2 h5 26. Qe4 Rg4 27. Qf5 Rb8 28. Rcc2 Rb5 29. d5 f6 30. Qxh5 g6 31. Qh6 Rxd5 32. e4 Rd1+ 33. Rf1 Bc5+ 34. Kh1 Rxf1+ 0-1

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2002.08.06"]
[Round "2"]
[White "Tan, Kevin"]
[Black "Koekoek, Arjen"]
[Result "1-0"]
[ECO "B32"]
[WhiteElo "2221"]
[PlyCount "51"]
[EventDate "2002.08.05"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2005"]
[Source "ChessBase"]
[SourceDate "2004.11.15"]
[SourceVersion "1"]
[SourceVersionDate "2004.11.15"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nb5 a6 6. Nd6+ Bxd6 7. Qxd6 Qf6 8. Qd2 Qg6 9. Nc3 Nge7 10. h4 h5 11. Rh3 Qg4 12. Rg3 Qxh4 13. Qd1 Qf6 14. Bg5 Qe6 15. Nd5 Nxd5 16. exd5 Qd6 17. dxc6 Qxc6 18. c4 f6 19. Bd2 g5 20. Qc2 Kf7 21. 0-0-0 a5 22. Bd3 d6 23. Be4 Qc7 24. Bd5+ Be6 25. Qe4 Rac8 26. Bxg5 1-0

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2002.08.05"]
[Round "1"]
[White "Rensen, Michiel"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B32"]
[PlyCount "80"]
[EventDate "2002.08.05"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2005"]
[Source "ChessBase"]
[SourceDate "2004.11.15"]
[SourceVersion "1"]
[SourceVersionDate "2004.11.15"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nf3 Nf6 6. Bd3 Be7 7. Nc3 0-0 8. Be3 d6 9. h3 Be6 10. Ng5 Qd7 11. 0-0 h6 12. Nxe6 fxe6 13. Bc4 Rfd8 14. Qf3 Na5 15. Bb5 Qc7 16. Qg3 Kh7 17. f4 exf4 18. Bxf4 Nh5 19. Qg4 Nxf4 20. Rxf4 Bg5 21. Rf3 Qe7 22. Raf1 Kg8 23. Bd3 Nc6 24. Qh5 Ne5 25. Rg3 Rf8 26. Nb5 Bf4 27. Rxf4 Rxf4 28. Qxh6 Rf6 29. Qe3 a6 30. Nd4 b5 31. a3 Qa7 32. c3 Nxd3 33. Qxd3 e5 34. Kh2 exd4 35. cxd4 Qc7 36. Qb3+ Qc4 37. Qe3 Qf7 38. h4 Rf4 39. Rg5 Rxh4+ 40. Kg3 Rh5 0-1

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2001.??.??"]
[Round "1"]
[White "De Bruijn, Thijs"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B20"]
[PlyCount "97"]
[EventDate "2001.08.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. Bc4 e6 4. Nc3 a6 5. a4 d6 6. d3 Nf6 7. 0-0 Be7 8. Be3 d5 9. e5 Nd7 10. Bxd5 exd5 11. Nxd5 Ndxe5 12. Nxe5 Qxd5 13. Nc4 Qd8 14. Re1 Be6 15. Nd2 0-0 16. Ne4 b6 17. c3 Ne5 18. d4 Nc4 19. Qc2 Nxe3 20. fxe3 Bf5 21. Nf6+ Bxf6 22. Qxf5 Qc8 23. Qh5 Re8 24. Rad1 Qc6 25. b3 Rad8 26. d5 Qd6 27. c4 Re5 28. Qf3 Rde8 29. e4 Rg5 30. Rf1 Re7 31. Qh3 Qd7 32. Qf3 Qg4 33. Qxg4 Rxg4 34. d6 Rd7 35. Rfe1 Bd4+ 36. Kh1 Rxd6 37. e5 Bxe5 38. Rxd6 Bxd6 39. Re8+ Bf8 40. Ra8 Re4 41. h3 a5 42. Rb8 Re6 43. Kg1 f5 44. Kf2 Kf7 45. Rb7+ Be7 46. g3 g5 47. Kf3 h5 48. g4 fxg4+ 49. hxg4 0-1

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2001.??.??"]
[Round "5"]
[White "Groenewold, Jan Joris"]
[Black "Koekoek, Arjen"]
[Result "1-0"]
[ECO "A14"]
[PlyCount "83"]
[EventDate "2001.08.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. Nf3 c5 2. g3 e6 3. Bg2 d5 4. c4 Nf6 5. 0-0 Be7 6. d4 b6 7. dxc5 Bxc5 8. cxd5 exd5 9. b4 Be7 10. Nd4 0-0 11. Qb3 Bb7 12. Rd1 Nc6 13. Nxc6 Bxc6 14. Nc3 Qd6 15. b5 Bb7 16. Nxd5 Bxd5 17. Bxd5 Nxd5 18. Rxd5 Qe6 19. Be3 Rac8 20. Rad1 Rc7 21. Bf4 Rc5 22. Rxc5 Qxb3 23. axb3 Bxc5 24. Ra1 Ra8 25. Ra4 f6 26. e3 Rd8 27. Rc4 g5 28. Bc7 Rd1+ 29. Kg2 Rb1 30. Rc3 Kf7 31. g4 Ke6 32. Rd3 Ra1 33. Bb8 Ra2 34. Kg3 Ke7 35. h3 Ra1 36. Kg2 Ra2 37. Kf3 Ra1 38. Ke4 Ra5 39. Kd5 Rxb5 40. Kc6 Ra5 41. Rd7+ Ke6 42. Rxa7 1-0

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2001.??.??"]
[Round "4"]
[White "Koekoek, Arjen"]
[Black "Ammerlaan, Richard"]
[Result "1-0"]
[ECO "B01"]
[PlyCount "59"]
[EventDate "2001.08.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c6 2. c4 d5 3. exd5 Nf6 4. d6 exd6 5. d4 d5 6. Nc3 Be7 7. Nf3 0-0 8. Ne5 Be6 9. b3 Bb4 10. Bb2 Ne4 11. Rc1 Re8 12. a3 Bxc3+ 13. Bxc3 f6 14. Nf3 dxc4 15. bxc4 Bxc4 16. Bxc4+ Kh8 17. 0-0 Nd7 18. Re1 Nb6 19. Bd3 Nxc3 20. Rxe8+ Qxe8 21. Rxc3 Nd5 22. Rc1 Rd8 23. Qc2 g6 24. Re1 Qf8 25. Qc5 Qf7 26. Bc4 Rd7 27. Bxd5 cxd5 28. Qxa7 g5 29. Qb8+ Kg7 30. Qe8 1-0

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2001.??.??"]
[Round "2"]
[White "Koekoek, Arjen"]
[Black "Van Beek, Alexander"]
[Result "0-1"]
[ECO "B40"]
[BlackElo "2262"]
[PlyCount "80"]
[EventDate "2001.08.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Bc5 5. Be3 Qb6 6. Nb5 Bxe3 7. fxe3 Nf6 8. Qd4 Ke7 9. N1c3 Qxd4 10. exd4 a6 11. e5 Ne8 12. Na3 b5 13. Ne4 Bb7 14. Nc5 Bc6 15. c4 d6 16. Nd3 Nd7 17. Nb4 Be4 18. cxb5 dxe5 19. Nc6+ Kd6 20. Nc4+ Kc7 21. N6xe5 axb5 22. Nxd7 bxc4 23. Ne5 Nd6 24. Bxc4 f6 25. Rc1 fxe5 26. Bd5+ Kd7 27. Bxa8 Rxa8 28. dxe5 Nf7 29. 0-0 Bg6 30. a3 Nxe5 31. Rc5 Nd3 32. Rd1 Ke7 33. Rb5 e5 34. Rd5 e4 35. Kf1 Nxb2 36. Rd7+ Kf6 37. R1d6+ Ke5 38. Rd5+ Kf4 39. Rxg7 Rxa3 40. g3+ Kf3 0-1

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2001.??.??"]
[Round "8"]
[White "Koekoek, Arjen"]
[Black "Van Dijk, Martin"]
[Result "1/2-1/2"]
[ECO "C25"]
[PlyCount "53"]
[EventDate "2001.08.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 e5 2. Nc3 Bc5 3. f4 exf4 4. Nf3 g5 5. d4 Bb4 6. Bc4 Bxc3+ 7. bxc3 c6 8. d5 d6 9. Qd4 f6 10. dxc6 Nxc6 11. Qd5 Nh6 12. Ba3 Qa5 13. Qxa5 Nxa5 14. Bd5 Ke7 15. h4 Ng4 16. hxg5 Be6 17. gxf6+ Nxf6 18. Bxe6 Kxe6 19. Ng5+ Kd7 20. Nf7 Nc4 21. Bxd6 Nxd6 22. Nxh8 Rxh8 23. e5 Re8 24. 0-0 Rxe5 25. Rxf4 Nd5 26. Rh4 h5 27. c4 1/2-1/2

[Event "Hengelo op U20"]
[Site "Hengelo"]
[Date "2001.??.??"]
[Round "6"]
[White "Koekoek, Arjen"]
[Black "Van Dommelen, Martin"]
[Result "1/2-1/2"]
[ECO "C25"]
[PlyCount "10"]
[EventDate "2001.08.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2008"]
[Source "ChessBase"]
[SourceDate "2007.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2007.11.25"]
[SourceQuality "1"]

1. e4 e5 2. Nc3 Nc6 3. f4 Bb4 4. Nf3 Bxc3 5. bxc3 exf4 1/2-1/2

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2001.??.??"]
[Round "3"]
[White "Van der Berg, Wessel"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B32"]
[PlyCount "58"]
[EventDate "2001.08.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nb5 a6 6. Nd6+ Bxd6 7. Qxd6 Qf6 8. Qd1 Qg6 9. Nc3 Nge7 10. Be3 d6 11. Qf3 Be6 12. Bd3 Nb4 13. Qg3 Qxg3 14. hxg3 Nxd3+ 15. cxd3 0-0 16. Ke2 f5 17. Rh2 b5 18. Rah1 h6 19. exf5 Nxf5 20. b3 d5 21. Bd2 Rac8 22. Rc1 Nd4+ 23. Ke3 b4 24. Nb1 Rxc1 25. Bxc1 Rc8 26. Bd2 Rc2 27. Rh5 Nf5+ 28. Ke2 Nxg3+ 29. Kd1 Rxd2+ 0-1

[Event "Hengelo U20 op"]
[Site "Hengelo"]
[Date "2001.??.??"]
[Round "7"]
[White "Veltman, Anne"]
[Black "Koekoek, Arjen"]
[Result "1-0"]
[ECO "B32"]
[PlyCount "75"]
[EventDate "2001.08.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nb5 a6 6. Nd6+ Bxd6 7. Qxd6 Qf6 8. Qd3 Nge7 9. Be3 d5 10. exd5 Nb4 11. Qd2 Nbxd5 12. Bc4 Be6 13. Bg5 Qg6 14. Bxe7 Nxe7 15. Bxe6 Qxe6 16. Nc3 Rd8 17. Qe2 Nf5 18. 0-0 Nd4 19. Qe4 f5 20. Qxb7 0-0 21. Rad1 Rd7 22. Qb4 Nxc2 23. Qa4 Nd4 24. Rfe1 Rfd8 25. Re3 f4 26. Re4 f3 27. Rde1 Qg6 28. Qc4+ Kh8 29. g3 Nc2 30. Rc1 Qh6 31. Qf1 Rd2 32. Rxe5 Rxf2 33. Kxf2 Rd2+ 34. Ne2 Qxh2+ 35. Kxf3 Rd3+ 36. Kg4 Ne3+ 37. Rxe3 h5+ 38. Kf3 1-0

[Event "NED-ch U16 op"]
[Site "Hengelo"]
[Date "2000.08.12"]
[Round "9"]
[White "Porte, Henrik"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "A85"]
[PlyCount "60"]
[EventDate "2000.08.07"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. d4 f5 2. c4 g6 3. Nc3 Nf6 4. Nf3 Bg7 5. Bg5 d6 6. e3 0-0 7. Be2 Nbd7 8. 0-0 e5 9. dxe5 dxe5 10. Nd5 c6 11. Nxf6+ Bxf6 12. Bxf6 Qxf6 13. b4 Nb6 14. c5 Nd5 15. Bc4 Be6 16. Qb3 g5 17. Qb2 Rae8 18. Nxe5 b5 19. Bxd5 Bxd5 20. Nd3 Qe6 21. Qd4 f4 22. exf4 gxf4 23. Rae1 Qg4 24. f3 Qf5 25. Re5 Rxe5 26. Nxe5 Bxa2 27. Nxc6 Re8 28. Nxa7 Bc4 29. Rd1 Qe6 30. c6 Qe1+ 0-1

[Event "NED-ch U16 op"]
[Site "Hengelo"]
[Date "2000.08.11"]
[Round "8"]
[White "Koekoek, Arjen"]
[Black "Holland, Remco"]
[Result "1-0"]
[ECO "C25"]
[PlyCount "113"]
[EventDate "2000.08.07"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 e5 2. Nc3 Nc6 3. f4 exf4 4. h4 Be7 5. Nf3 d6 6. d3 Bg4 7. Bxf4 Bxh4+ 8. g3 Be7 9. Be2 Qd7 10. d4 0-0-0 11. d5 Nb8 12. Qd4 c5 13. Qc4 a6 14. a4 f5 15. e5 Bxf3 16. e6 Qc7 17. Bxf3 Re8 18. Bh5 Rf8 19. Qd3 c4 20. Qe3 h6 21. Bg6 Nf6 22. a5 Ng4 23. Qd2 Bf6 24. Na4 Be5 25. Nb6+ Kd8 26. Bxe5 Nxe5 27. Bh5 g6 28. Be2 g5 29. Ra4 f4 30. Nxc4 f3 31. Nxe5 dxe5 32. Bd3 e4 33. Rxe4 Qxg3+ 34. Qf2 Qxf2+ 35. Kxf2 Ke7 36. Rh3 h5 37. Rxf3 h4 38. Rxf8 Rxf8+ 39. Kg2 Kf6 40. c4 Rg8 41. Kh3 Re8 42. Kg4 Rh8 43. Re3 Re8 44. Bf5 Rd8 45. d6 Nc6 46. e7 Nxe7 47. dxe7 Re8 48. Re6+ Kf7 49. Kxg5 Rxe7 50. Rxe7+ Kxe7 51. Kxh4 Kd6 52. b4 Kc6 53. Kg4 b6 54. axb6 Kxb6 55. Kf4 a5 56. bxa5+ Kxa5 57. Ke4 1-0

[Event "NED-ch U16 op"]
[Site "Hengelo"]
[Date "2000.08.11"]
[Round "7"]
[White "Koekoek, Arjen"]
[Black "Sminia, Jelmer"]
[Result "1/2-1/2"]
[ECO "C30"]
[PlyCount "98"]
[EventDate "2000.08.07"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 e5 2. Nc3 Nc6 3. f4 d6 4. d3 Nf6 5. Nf3 Be7 6. Be2 Bg4 7. 0-0 Qd7 8. Be3 0-0-0 9. d4 Bxf3 10. Bxf3 a6 11. d5 Nb8 12. a4 exf4 13. Bxf4 h5 14. Qd4 c5 15. Qc4 Qc7 16. Rfb1 Nfd7 17. a5 g5 18. Bg3 g4 19. Be2 h4 20. Bf4 Rdg8 21. b4 cxb4 22. Qxb4 Qc5+ 23. Kh1 Qxb4 24. Rxb4 Nc5 25. e5 Nbd7 26. exd6 Bf6 27. Rc4 Kd8 28. Be3 Re8 29. Bd4 Bxd4 30. Rxd4 f5 31. Bd3 Re5 32. Rf1 Nxd3 33. Rxd3 Nc5 34. Rd2 Kd7 35. Ne2 Ne4 36. Rd3 g3 37. Kg1 Nf2 38. Rd2 Ne4 39. Rd3 gxh2+ 40. Kxh2 Kxd6 41. Nd4 Ng3 42. Rf2 Rh5 43. Rd1 Kc5 44. Ne6+ Kd6 45. Nd4 Re3 46. Nb3 Ne4 47. Rf3 Rc3 48. Rxc3 Nxc3 49. Rd3 Ne4 1/2-1/2

[Event "NED-ch U16 op"]
[Site "Hengelo"]
[Date "2000.08.10"]
[Round "6"]
[White "Tan, Kevin"]
[Black "Koekoek, Arjen"]
[Result "1-0"]
[ECO "B32"]
[PlyCount "72"]
[EventDate "2000.08.07"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nb5 a6 6. Nd6+ Bxd6 7. Qxd6 Qf6 8. Qxf6 Nxf6 9. Bd3 d5 10. exd5 Nxd5 11. c3 0-0 12. 0-0 Be6 13. Na3 f5 14. Rd1 Rad8 15. Bc4 b5 16. Bb3 h6 17. Be3 e4 18. Nc2 Bf7 19. Bc5 Rfe8 20. Nd4 Nxd4 21. Bxd4 Nf4 22. Rd2 Bc4 23. Bxc4+ bxc4 24. b3 Nd3 25. bxc4 Rc8 26. Rb1 Re6 27. Rb7 Rg6 28. f3 Ne1 29. Kf1 exf3 30. g3 Re8 31. c5 f4 32. gxf4 Ng2 33. f5 Rg4 34. c6 Rh4 35. c7 Re1+ 36. Kf2 Rxh2 1-0

[Event "NED-ch U16 op"]
[Site "Hengelo"]
[Date "2000.08.09"]
[Round "4"]
[White "Den Heeten, Djurre"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B25"]
[PlyCount "124"]
[EventDate "2000.08.07"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 c5 2. Nc3 d6 3. g3 g6 4. Bg2 Bg7 5. d3 Nc6 6. Nce2 e6 7. f4 Nge7 8. c3 Bd7 9. Be3 0-0 10. Nf3 b5 11. 0-0 Rb8 12. g4 f5 13. gxf5 exf5 14. Ng3 b4 15. exf5 Nxf5 16. Nxf5 Rxf5 17. cxb4 Rxb4 18. Rb1 Bxb2 19. a3 Rb6 20. Qc2 Bf6 21. Ng5 Bxg5 22. fxg5 Ne5 23. Be4 Rf8 24. Rxf8+ Qxf8 25. Rf1 Qe7 26. Rf6 Bc6 27. Bxc6 Rxc6 28. Qb3+ Kg7 29. Re6 Qc7 30. Qd5 Rb6 31. Bf4 Rb1+ 32. Kf2 Qf7 33. Ke3 Re1+ 34. Kd2 Nf3+ 35. Qxf3 Rxe6 36. Qg3 Qd7 37. Qg4 Qe7 38. Qf3 Qf7 39. Qg3 d5 40. Be5+ Kg8 41. d4 cxd4 42. Bxd4 Re8 43. Bf6 Qe6 44. Qc7 Qe1+ 45. Kc2 Qf2+ 46. Kc3 Re3+ 47. Kb4 Re4+ 48. Kb5 Qb6+ 49. Qxb6 axb6 50. a4 d4 51. Kc4 d3+ 52. Kxd3 Rxa4 53. Be5 Rg4 54. Bc7 b5 55. Kc3 Rxg5 56. Kb4 Kf7 57. Bd8 Rf5 58. Bc7 h5 59. h4 g5 60. hxg5 Rxg5 61. Bd8 Rg4+ 62. Kxb5 h4 0-1

[Event "NED-ch U16 op"]
[Site "Hengelo"]
[Date "2000.08.09"]
[Round "5"]
[White "Koekoek, Arjen"]
[Black "Kamstra, Jippe"]
[Result "1-0"]
[ECO "B92"]
[PlyCount "59"]
[EventDate "2000.08.07"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Be2 e5 7. Nf3 Be6 8. Ng5 Nc6 9. Nxe6 fxe6 10. 0-0 Be7 11. Bh5+ Kd7 12. Be3 Qa5 13. a3 Rag8 14. b4 Qd8 15. b5 Nd4 16. bxa6 Nxh5 17. Qxh5 Nxc2 18. Qe2 bxa6 19. Qxc2 Ke8 20. Qa4+ Kf7 21. f4 h6 22. f5 Bg5 23. fxe6+ Kg6 24. Bxg5 hxg5 25. Qxa6 Qc7 26. Qd3 Qc5+ 27. Kh1 Rh4 28. g3 Rxh2+ 29. Kxh2 Rh8+ 30. Kg2 1-0

[Event "NED-ch U16 op"]
[Site "Hengelo"]
[Date "2000.08.08"]
[Round "2"]
[White "Koekoek, Arjen"]
[Black "Van Rijn, Luuk"]
[Result "1/2-1/2"]
[ECO "B02"]
[PlyCount "68"]
[EventDate "2000.08.07"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 Nf6 2. Nc3 c6 3. e5 Nd5 4. Nxd5 cxd5 5. f4 e6 6. Nf3 b6 7. Be2 Ba6 8. 0-0 d6 9. d4 Be7 10. Bxa6 Nxa6 11. Qd3 Nc7 12. Bd2 Qd7 13. exd6 Qxd6 14. a3 a5 15. Rae1 h6 16. f5 0-0 17. Ne5 Bf6 18. Bf4 Qd8 19. Qh3 exf5 20. Qxf5 Ne6 21. Be3 Qe7 22. c3 Qc7 23. Bxh6 Bxe5 24. Rxe5 gxh6 25. Qf6 Ng7 26. Qxh6 f6 27. Rxd5 Qe7 28. Qg6 Rf7 29. Rh5 Qe3+ 30. Kh1 Qe2 31. Rhf5 Qe4 32. Qg3 Re8 33. h4 Qe6 34. h5 Kf8 1/2-1/2

[Event "NED-ch U16 op"]
[Site "Hengelo"]
[Date "2000.08.08"]
[Round "3"]
[White "Verboom, Linda"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B46"]
[PlyCount "82"]
[EventDate "2000.08.07"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. Nc3 e6 4. d4 cxd4 5. Nxd4 a6 6. Be3 Bb4 7. Qd2 Nf6 8. f3 d5 9. Nxc6 bxc6 10. e5 Nd7 11. a3 Ba5 12. b4 Bb6 13. Bxb6 Qxb6 14. f4 Bb7 15. Bd3 c5 16. Na4 Qa7 17. bxc5 Nxc5 18. Nxc5 Qxc5 19. Ke2 a5 20. Rhb1 Qc7 21. Bb5+ Bc6 22. Bxc6+ Qxc6 23. Qd3 0-0 24. Rb2 Rac8 25. Rc1 d4 26. Kf2 Qa4 27. Rb3 Rc3 28. Qd1 Rxb3 29. cxb3 Qxa3 30. Ra1 Qb2+ 31. Kf1 Qc3 32. Ra4 Rd8 33. Rc4 Qe3 34. g3 h6 35. b4 axb4 36. Rxb4 d3 37. Rb3 Qe4 38. Kf2 Qd4+ 39. Kf1 Qc4 40. Rb2 d2+ 41. Kg2 Qc1 0-1

[Event "NED-ch U16 op"]
[Site "Hengelo"]
[Date "2000.08.07"]
[Round "1"]
[White "De Jong, Bert"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "A28"]
[PlyCount "42"]
[EventDate "2000.08.07"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. c4 e5 2. Nc3 Nf6 3. d3 Bc5 4. Nf3 d6 5. e3 Bg4 6. Be2 Nc6 7. a3 a5 8. Nd2 Bxe2 9. Qxe2 0-0 10. 0-0 d5 11. Nf3 e4 12. dxe4 dxe4 13. Rd1 exf3 14. Rxd8 fxe2 15. Rxf8+ Rxf8 16. Nxe2 Rd8 17. g3 Ne5 18. Nd4 Bxd4 19. exd4 Nf3+ 20. Kg2 Nxd4 21. Bf4 Ne6 0-1

[Event "NED-ch U16"]
[Site "Leiden"]
[Date "2000.05.06"]
[Round "9"]
[White "Koekoek, Arjen"]
[Black "Wakkee, Colijn"]
[Result "1-0"]
[ECO "C47"]
[PlyCount "41"]
[EventDate "2000.05.01"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Nf6 5. Nc3 Be7 6. Be2 0-0 7. Nxc6 dxc6 8. Be3 Be6 9. 0-0 h6 10. f4 Bb4 11. f5 Bd7 12. e5 Bxc3 13. bxc3 Nd5 14. Bd2 Re8 15. c4 Nb6 16. f6 g5 17. Bb4 Rxe5 18. Bd3 Re6 19. Qf3 Kh8 20. Qh5 Rxf6 21. Bc3 1-0

[Event "NED-ch U16"]
[Site "Leiden"]
[Date "2000.05.05"]
[Round "8"]
[White "Edeling, Jeroen"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B23"]
[PlyCount "78"]
[EventDate "2000.05.01"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. f4 e6 3. Nc3 Nc6 4. Bb5 Nge7 5. Nf3 a6 6. Bxc6 Nxc6 7. 0-0 Be7 8. d3 0-0 9. Qe1 d5 10. Qg3 d4 11. Nd1 f5 12. e5 b5 13. a3 Bb7 14. Nf2 Rc8 15. Nh3 h6 16. Qg6 Qd7 17. Bd2 Bd8 18. Nf2 Qf7 19. Qg3 Qh5 20. b4 c4 21. c3 Bb6 22. dxc4 bxc4 23. cxd4 Nxd4 24. Nxd4 Bxd4 25. Bc3 Rfd8 26. Bxd4 Rxd4 27. Rfd1 Rxd1+ 28. Rxd1 Qf7 29. Rd6 Bd5 30. Nd1 Qa7+ 31. Kf1 Qd4 32. Nc3 Qd2 33. Rd7 Bxg2+ 34. Qxg2 Qxd7 35. Qe2 Qd3 36. Qxd3 cxd3 37. Nd1 Rc2 38. Nf2 d2 39. Nd1 Ra2 0-1

[Event "NED-ch U16"]
[Site "Leiden"]
[Date "2000.05.05"]
[Round "7"]
[White "Koekoek, Arjen"]
[Black "Hummel, Erik Jan"]
[Result "0-1"]
[ECO "C01"]
[PlyCount "89"]
[EventDate "2000.05.01"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 e6 2. d4 d5 3. exd5 exd5 4. Bd3 Nc6 5. c3 Bd6 6. Nf3 Bg4 7. 0-0 Nge7 8. Re1 Qd7 9. Bg5 f6 10. Be3 0-0-0 11. a3 Nf5 12. b4 Nce7 13. c4 Nxe3 14. fxe3 dxc4 15. Bxc4 Qf5 16. Qb3 Kb8 17. Nbd2 Qh5 18. a4 g5 19. h3 Bxf3 20. Nxf3 f5 21. Ne5 Bxe5 22. dxe5 g4 23. e4 f4 24. Be2 f3 25. hxg4 f2+ 26. Kxf2 Qh2 27. Bf3 Nc6 28. Rh1 Qf4 29. Rad1 Nxe5 30. Ke2 Nxg4 31. Bxg4 Qxg4+ 32. Qf3 Qe6 33. Rxd8+ Rxd8 34. Kf2 Qb6+ 35. Kg3 Rg8+ 36. Kh2 Qxb4 37. Rf1 Qd6+ 38. g3 h5 39. Qf4 Qe7 40. e5 a6 41. Qf6 Re8 42. Rf5 c5 43. Rxh5 c4 44. Rh4 c3 45. Qd6+ 0-1

[Event "NED-ch U16"]
[Site "Leiden"]
[Date "2000.05.04"]
[Round "6"]
[White "Freeke, Matthieu"]
[Black "Koekoek, Arjen"]
[Result "1/2-1/2"]
[ECO "B22"]
[PlyCount "51"]
[EventDate "2000.05.01"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. c3 d5 3. exd5 Qxd5 4. d4 Nf6 5. Nf3 Bg4 6. Be2 e6 7. Be3 Nbd7 8. 0-0 Be7 9. h3 Bh5 10. Nbd2 Rc8 11. Bc4 Qd6 12. Bb3 0-0 13. Qe1 Bg6 14. Qe2 Nd5 15. a3 Nxe3 16. fxe3 f5 17. Rae1 b5 18. e4 c4 19. Bc2 f4 20. Kh1 a6 21. Rd1 Qc7 22. Rde1 Rcd8 23. Ng1 Bf6 24. Qf2 e5 25. b4 Qb6 26. Re2 1/2-1/2

[Event "NED-ch U16"]
[Site "Leiden"]
[Date "2000.05.03"]
[Round "5"]
[White "Koekoek, Arjen"]
[Black "Van Assendelft, Floris"]
[Result "0-1"]
[ECO "B73"]
[PlyCount "84"]
[EventDate "2000.05.01"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 g6 6. Be3 Bg7 7. Be2 0-0 8. 0-0 Nc6 9. Qd2 Bd7 10. f4 Rc8 11. Nxc6 Bxc6 12. Bf3 a6 13. a4 Qc7 14. a5 Nd7 15. Bd4 e5 16. Be3 exf4 17. Bxf4 Ne5 18. Be2 b5 19. Rfd1 Rfd8 20. Be3 Qb7 21. Nd5 Bxd5 22. exd5 Nc4 23. Bxc4 Rxc4 24. c3 b4 25. cxb4 Rxb4 26. Bb6 Rxb2 27. Qe3 Rxb6 28. Qxb6 Qxb6+ 29. axb6 Bxa1 30. Rxa1 Rb8 31. Rxa6 Kg7 32. b7 Rxb7 33. Rxd6 Kf8 34. Rc6 Ke7 35. Kf2 Rd7 36. Rc5 Kd6 37. Ra5 Ke5 38. Kf3 Rxd5 39. Rxd5+ Kxd5 40. Kf4 h6 41. g4 f6 42. h3 Ke6 0-1

[Event "NED-ch U16"]
[Site "Leiden"]
[Date "2000.05.03"]
[Round "4"]
[White "Van der Eijk, Martijn"]
[Black "Koekoek, Arjen"]
[Result "1-0"]
[ECO "A00"]
[PlyCount "101"]
[EventDate "2000.05.01"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. Nc3 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 d5 5. Bf4 a6 6. e4 Nf6 7. e5 Ne4 8. Nxc6 bxc6 9. Nxe4 dxe4 10. Qxd8+ Kxd8 11. Bc4 Bc5 12. Bxf7 Ke7 13. Bb3 Be6 14. Rd1 Bxb3 15. axb3 Rhf8 16. g3 Ke6 17. 0-0 h6 18. Rfe1 g5 19. Be3 Bb4 20. c3 Be7 21. Rd4 Kxe5 22. Bd2 Kf5 23. Rdxe4 Bd6 24. f4 g4 25. c4 Rab8 26. c5 Bxc5+ 27. Kf1 Bd6 28. Bc3 Rxb3 29. Re6 Rxc3 30. bxc3 Rh8 31. Re8 Rh7 32. Ra8 h5 33. Rxa6 c5 34. Ra2 Rh6 35. Rae2 Rg6 36. c4 Rg8 37. Re8 Rxe8 38. Rxe8 Kg6 39. Kg2 Kf5 40. Rg8 Ke4 41. Rg5 Kd4 42. f5 Kxc4 43. f6 Kd3 44. Rxh5 c4 45. Rd5+ Ke2 46. Rxd6 cxd6 47. f7 c3 48. f8Q c2 49. Qe7+ Kd2 50. Qxd6+ Kc3 51. Kf2 1-0

[Event "NED-ch U16"]
[Site "Leiden"]
[Date "2000.05.02"]
[Round "2"]
[White "Boelaars, Ilja"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B46"]
[PlyCount "32"]
[EventDate "2000.05.01"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Nc3 a6 6. Be2 Nge7 7. f4 Nxd4 8. Qxd4 Nc6 9. Qf2 Be7 10. Be3 0-0 11. 0-0 d5 12. Rad1 d4 13. Bxd4 Nxd4 14. Qxd4 Qxd4+ 15. Rxd4 Bc5 16. Rfd1 Rd8 0-1

[Event "NED-ch U16"]
[Site "Leiden"]
[Date "2000.05.02"]
[Round "3"]
[White "Koekoek, Arjen"]
[Black "De Bode, Christian"]
[Result "1-0"]
[ECO "C29"]
[PlyCount "91"]
[EventDate "2000.05.01"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 e5 2. Nc3 Nc6 3. f4 Nf6 4. fxe5 Nxe5 5. d4 Bb4 6. dxe5 Nxe4 7. Qd4 Qh4+ 8. g3 c5 9. Qxb4 cxb4 10. gxh4 bxc3 11. Bg2 Nc5 12. bxc3 0-0 13. Be3 Re8 14. Bd4 d6 15. 0-0-0 Bg4 16. Bf3 Bxf3 17. Nxf3 Ne4 18. Rhe1 dxe5 19. Rxe4 exd4 20. Rxe8+ Rxe8 21. cxd4 f6 22. Re1 Rxe1+ 23. Nxe1 Kf7 24. c4 Ke6 25. Kd2 Kf5 26. Nf3 Ke4 27. d5 Kf5 28. Nd4+ Ke5 29. Ke3 a6 30. Ne6 b5 31. cxb5 axb5 32. Nc7 b4 33. Na6 Kxd5 34. Nxb4+ Kc5 35. Nd3+ Kb5 36. Nf4 Ka4 37. Nh5 Ka3 38. Nxg7 Kxa2 39. Nh5 Kb3 40. Nxf6 Kc4 41. Ke4 Kc5 42. Ke5 h6 43. Ng8 Kc6 44. Nxh6 Kd7 45. Kf6 Ke8 46. Kg7 1-0

[Event "NED-ch U16"]
[Site "Leiden"]
[Date "2000.05.01"]
[Round "1"]
[White "Koekoek, Arjen"]
[Black "Erwich, Frank"]
[Result "0-1"]
[ECO "B06"]
[BlackElo "2224"]
[PlyCount "58"]
[EventDate "2000.05.01"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 g6 2. d4 Bg7 3. Nf3 c6 4. Bg5 d5 5. e5 f6 6. Bf4 Nh6 7. Qd2 Nf7 8. exf6 exf6 9. Qe3+ Kd7 10. Qd3 Re8+ 11. Be2 b6 12. Nc3 Ba6 13. Qd2 Bxe2 14. Nxe2 Qe7 15. Be3 Nd6 16. b3 Nf5 17. 0-0 Nxe3 18. fxe3 Qxe3+ 19. Qxe3 Rxe3 20. Rae1 Bh6 21. g4 Na6 22. a3 Rae8 23. Kf2 R3e4 24. g5 Bxg5 25. Nxg5 fxg5 26. c3 Nc7 27. a4 Ne6 28. Ng3 Rxe1 29. Rxe1 Nf4 0-1

[Event "NED U16 op"]
[Site "Hengelo"]
[Date "1999.08.14"]
[Round "9"]
[White "Koekoek, Arjen"]
[Black "Van Kempen, Roderick"]
[Result "1-0"]
[ECO "B84"]
[PlyCount "146"]
[EventDate "1999.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Be3 Nbd7 7. Be2 e6 8. 0-0 Be7 9. f4 Qc7 10. f5 Nc5 11. Bf3 e5 12. Nde2 Rb8 13. g4 h6 14. Ng3 b5 15. a3 Bb7 16. Qd2 Rd8 17. Qg2 Rd7 18. Rad1 Ba8 19. Rd2 Nb7 20. Qf2 Bd8 21. a4 Na5 22. axb5 Nc4 23. Rdd1 Nxe3 24. Qxe3 axb5 25. Nxb5 Qc6 26. Qe2 Bb6+ 27. Kh1 Ke7 28. c4 Bb7 29. b3 Ba6 30. Nc3 Bd4 31. Qc2 Rb8 32. Nge2 Ba7 33. Ra1 Rdb7 34. Rab1 Be3 35. Rfd1 Rb4 36. Nd5+ Nxd5 37. exd5 Qc5 38. Nc3 Bf2 39. Ne4 Qe3 40. Qxf2 Qxf2 41. Nxf2 Bxc4 42. Be4 Rxb3 43. Rxb3 Rxb3 44. Rc1 Be2 45. Kg2 Re3 46. Re1 Bf3+ 47. Kf1 Rc3 48. Bxf3 Rxf3 49. Ke2 Rf4 50. Ke3 h5 51. h3 g6 52. fxg6 fxg6 53. gxh5 gxh5 54. Rg1 Kf7 55. Ne4 Rh4 56. Rf1+ Ke7 57. Rf3 Kd7 58. Rg3 Ke7 59. Kf3 Rf4+ 60. Ke3 Rh4 61. Kd3 Kd7 62. Rg6 Rxh3+ 63. Kc4 Rh4 64. Rxd6+ Kc7 65. Rc6+ Kd7 66. Kd3 Rh3+ 67. Ke2 h4 68. Re6 Rh1 69. Rxe5 h3 70. Rh5 Rh2+ 71. Kf3 Rh1 72. Nf2 Ra1 73. Nxh3 Ra4 1-0

[Event "NED U16 op"]
[Site "Hengelo"]
[Date "1999.08.13"]
[Round "7"]
[White "Koekoek, Arjen"]
[Black "Ammerlaan, Stefan"]
[Result "0-1"]
[ECO "B33"]
[PlyCount "112"]
[EventDate "1999.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 e5 6. Ndb5 d6 7. Nd5 Nxd5 8. exd5 Nb8 9. Be2 a6 10. Nc3 f5 11. 0-0 g6 12. Be3 f4 13. Bd2 Bf5 14. Bg4 Qg5 15. Bf3 Nd7 16. Ne4 Bxe4 17. Bxe4 Nf6 18. f3 h5 19. c4 h4 20. Qa4+ Kf7 21. Qb3 h3 22. Rf2 Rb8 23. g4 Nxe4 24. fxe4 Qxg4+ 25. Kh1 Be7 26. Raf1 g5 27. Ba5 Qd7 28. Qd1 Rbg8 29. Rg1 g4 30. Bd2 Bh4 31. Rff1 g3 32. hxg3 Bxg3 33. Qf3 Ke8 34. Be1 Qg7 35. a3 Qg4 36. Qxg4 Rxg4 37. Bb4 Kd7 38. Rf3 b6 39. Be1 Rhg8 40. Bc3 Ke7 41. Be1 Bxe1 42. Rxe1 Rg3 43. Rf2 Kf6 44. Kh2 R8g4 45. Kh1 Kg5 46. Rd1 Rg2 47. Rf3 R4g3 48. Rdd3 Kg4 49. Rxg3+ fxg3 50. b4 Ra2 51. Rd1 Rc2 52. c5 bxc5 53. bxc5 Rxc5 54. a4 Rc4 55. Re1 Rxa4 56. Rg1 Rb4 0-1

[Event "NED U16 op"]
[Site "Hengelo"]
[Date "1999.08.13"]
[Round "8"]
[White "Vlug, Marcel"]
[Black "Koekoek, Arjen"]
[Result "1-0"]
[ECO "B46"]
[PlyCount "89"]
[EventDate "1999.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 c5 2. d4 cxd4 3. Nf3 Nc6 4. Nxd4 e6 5. Nc3 a6 6. Be3 Bb4 7. a3 Ba5 8. Bd3 Nf6 9. 0-0 d6 10. Kh1 e5 11. Nxc6 bxc6 12. Bg5 h6 13. Bh4 g5 14. Bg3 Be6 15. Re1 Bb6 16. Qd2 Nd7 17. Rad1 Nc5 18. b4 Nxd3 19. Qxd3 Bc7 20. f3 0-0 21. h3 Qe7 22. Bf2 f5 23. Na4 Qf7 24. Nb2 fxe4 25. Qxe4 d5 26. Qe2 Bf5 27. Nd3 Rfe8 28. Nc5 e4 29. c3 a5 30. Ra1 Be5 31. Bd4 Bxd4 32. cxd4 axb4 33. axb4 Rab8 34. Rf1 e3 35. Ra4 Qh7 36. Rfa1 Bc2 37. Ra7 Qg6 38. R1a3 Rxb4 39. Rxe3 Reb8 40. Re6 Qf5 41. Re8+ Rxe8 42. Qxe8+ Qf8 43. Rg7+ Kxg7 44. Ne6+ Kf6 45. Qxf8+ 1-0

[Event "NED U16 op"]
[Site "Hengelo"]
[Date "1999.08.12"]
[Round "6"]
[White "Vivolo, Zeno"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B44"]
[PlyCount "132"]
[EventDate "1999.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. c4 Nf6 6. Nxc6 bxc6 7. e5 Qa5+ 8. Nc3 Qxe5+ 9. Be2 Be7 10. 0-0 0-0 11. f4 Bc5+ 12. Kh1 Qc7 13. Qe1 d5 14. Bd3 Ba6 15. Bc2 Bxc4 16. Rf3 Be7 17. Qh4 Ne4 18. Qh5 f5 19. Bxe4 dxe4 20. Rh3 h6 21. g4 fxg4 22. Qxg4 Kh8 23. Qg6 Rf6 24. Qxe4 Bd5 25. Nxd5 exd5 26. Qd4 Qb6 27. Qd3 Bd6 28. Be3 Bc5 29. Bd2 Bd4 30. Rb1 Re8 31. b3 Re4 32. Qg3 Rfe6 33. f5 Rf6 34. Bg5 Bf2 35. Qg2 Rd6 36. f6 Bd4 37. Bxh6 Rd7 38. Bxg7+ Kg8 39. Rh8+ Kf7 40. Rf8+ Ke6 41. Re8+ Kd6 42. Rxe4 dxe4 43. Qxe4 Kc7 44. Qf4+ Kb7 45. Rd1 Qc5 46. Qf3 Rf7 47. h4 Be5 48. Rf1 Qc2 49. Rf2 Qc1+ 50. Kg2 Qc5 51. h5 Bd4 52. Re2 Qg5+ 53. Qg3 Qd5+ 54. Qf3 Qg5+ 55. Kh3 Qxg7 56. fxg7 Rxf3+ 57. Kg4 Rf1 58. h6 Rg1+ 59. Kh3 Rg6 60. Re7+ Kb6 61. Rf7 Rxh6+ 62. Kg4 Rg6+ 63. Kf5 Rxg7 64. Rxg7 Bxg7 65. Ke4 Kb5 66. Kd3 Kb4 0-1

[Event "NED U16 op"]
[Site "Hengelo"]
[Date "1999.08.11"]
[Round "4"]
[White "Benning, Tim"]
[Black "Koekoek, Arjen"]
[Result "1-0"]
[ECO "B46"]
[PlyCount "71"]
[EventDate "1999.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 a6 6. Be2 Bb4 7. 0-0 Nge7 8. Kh1 0-0 9. f4 d5 10. exd5 Nxd5 11. Nxc6 bxc6 12. Ne4 Qe7 13. a3 Ba5 14. Bd3 f5 15. Ng5 h6 16. Nf3 c5 17. Ne5 Qe8 18. c4 Ne7 19. Be3 Bb6 20. b4 Bb7 21. Rb1 Rb8 22. Bc2 Rd8 23. Qe2 Ba8 24. Rfd1 Nc6 25. Rxd8 Qxd8 26. Nxc6 Bxc6 27. Bxc5 Re8 28. Rd1 Qc7 29. Bd6 Qf7 30. c5 Bb5 31. Bd3 Bxd3 32. Qxd3 Bd8 33. Qxa6 Qh5 34. Qd3 Bf6 35. c6 Rc8 36. c7 1-0

[Event "NED U16 op"]
[Site "Hengelo"]
[Date "1999.08.11"]
[Round "5"]
[White "Koekoek, Arjen"]
[Black "Hania, Renske"]
[Result "1/2-1/2"]
[ECO "B34"]
[PlyCount "125"]
[EventDate "1999.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 g6 5. Nc3 Bg7 6. Be3 Nf6 7. Be2 0-0 8. g4 d5 9. Nxc6 bxc6 10. e5 Ne4 11. Nxe4 dxe4 12. Qd4 Qa5+ 13. Qd2 Qxd2+ 14. Bxd2 Bxe5 15. 0-0-0 Rb8 16. c3 Be6 17. Kb1 Bd5 18. Be1 Rb7 19. b3 Be6 20. h3 a5 21. c4 Ra8 22. Kc2 f5 23. Bc3 Bxc3 24. Kxc3 Rf8 25. Rh2 Rd7 26. Rxd7 Bxd7 27. Kd4 Rd8 28. Ke3 c5 29. Rh1 Bc6 30. gxf5 gxf5 31. Rg1+ Kf7 32. Rg2 Kf6 33. h4 e5 34. f4 exf3 35. Bxf3 Bxf3 36. Kxf3 Rd3+ 37. Ke2 Rh3 38. Rg8 Rxh4 39. Rc8 Rh2+ 40. Kf3 Kg5 41. Rxc5 e4+ 42. Ke3 Rxa2 43. Rb5 h5 44. Rb8 Rc2 45. Rg8+ Kh4 46. Rf8 Rc3+ 47. Kd2 Rxb3 48. Rxf5 a4 49. Rf4+ Kg3 50. Rxe4 h4 51. c5 h3 52. Rxa4 h2 53. Ra1 Rb2+ 54. Kc3 Rg2 55. Rh1 Rg1 56. Rxh2 Kxh2 57. Kd4 Kg3 58. c6 Kf4 59. Kd5 Kf5 60. c7 Rc1 61. Kd6 Rd1+ 62. Ke7 Re1+ 63. Kd6 1/2-1/2

[Event "NED U16 op"]
[Site "Hengelo"]
[Date "1999.08.10"]
[Round "2"]
[White "Koekoek, Arjen"]
[Black "De Jong, Roderick"]
[Result "1-0"]
[ECO "C45"]
[PlyCount "45"]
[EventDate "1999.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Nge7 5. Bg5 Nxd4 6. Qxd4 Nc6 7. Qd2 Be7 8. Be3 d6 9. Be2 Be6 10. Nc3 0-0 11. 0-0 Bf6 12. f4 Ne7 13. f5 Bd7 14. Bg5 Nc6 15. Bxf6 Qxf6 16. Kh1 Ne5 17. Nd5 Qd8 18. f6 Be6 19. Ne7+ Kh8 20. fxg7+ Kxg7 21. Qg5+ Ng6 22. Qf6+ Kh6 23. Rf4 1-0

[Event "NED U16 op"]
[Site "Hengelo"]
[Date "1999.08.10"]
[Round "3"]
[White "Koekoek, Arjen"]
[Black "Sprenger, Wendelin"]
[Result "1/2-1/2"]
[ECO "C01"]
[PlyCount "150"]
[EventDate "1999.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 e6 2. d4 d5 3. exd5 exd5 4. Bd3 Bd6 5. Ne2 Qh4 6. Nbc3 c6 7. Be3 Nf6 8. Qd2 Ng4 9. g3 Qf6 10. h3 Nxe3 11. Qxe3+ Be6 12. f4 0-0 13. 0-0-0 Bf5 14. Bxf5 Qxf5 15. g4 Qd7 16. Qf3 Qc7 17. Rhf1 Nd7 18. g5 f6 19. g6 h6 20. f5 Rfe8 21. Rd3 Nb6 22. Nf4 Bxf4+ 23. Qxf4 Qxf4+ 24. Rxf4 Re7 25. b3 Rae8 26. Kd2 Nc8 27. Kc1 Nd6 28. Rff3 Re1+ 29. Kb2 R8e7 30. Na4 Kf8 31. Nc5 Ke8 32. Na4 b6 33. Nc3 Kd7 34. Nd1 a5 35. Ne3 Re2 36. Ng4 h5 37. Ne3 a4 38. Kc1 axb3 39. axb3 Re1+ 40. Kd2 Ra1 41. Ke2 Re4 42. Kf2 Nb5 43. Nf1 Nxd4 44. Ng3 Nxf3 45. Nxe4 Ne5 46. Rd2 h4 47. Nc3 Rh1 48. Kg2 Rh2+ 49. Kxh2 Nf3+ 50. Kg2 Nxd2 51. Kf2 Kd6 52. Ke3 Nf1+ 53. Kf4 b5 54. Ne2 c5 55. Nc3 Kc6 56. Kg4 Ne3+ 57. Kxh4 Nxf5+ 58. Kg4 Ne7 59. Kh5 b4 60. Ne2 Kd6 61. Nf4 c4 62. Kg4 cxb3 63. cxb3 d4 64. Kf3 f5 65. h4 Nd5 66. Nh5 Ke5 67. Nxg7 Kf6 68. Ne8+ Kxg6 69. Nd6 Ne7 70. Nb5 Nc6 71. Nd6 Na5 72. Kf4 Nxb3 73. Nxf5 d3 74. Ne3 Nd2 75. Nd1 b3 1/2-1/2

[Event "NED U16 op"]
[Site "Hengelo"]
[Date "1999.08.09"]
[Round "1"]
[White "Weijers, Ralf"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "C00"]
[PlyCount "74"]
[EventDate "1999.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 c5 2. f4 e6 3. Nf3 Nc6 4. c3 d5 5. e5 d4 6. Bb5 Qd5 7. 0-0 a6 8. Bxc6+ Qxc6 9. cxd4 cxd4 10. d3 Bd7 11. Nbd2 Nh6 12. Kh1 Nf5 13. Nb3 Qb6 14. g4 Ne3 15. Bxe3 dxe3 16. d4 e2 17. Qxe2 Bb5 18. Qd2 Bxf1 19. Rxf1 Bb4 20. Qd1 0-0 21. h4 f5 22. exf6 Rxf6 23. Ne5 Raf8 24. Qc1 Rd8 25. Qc4 Qb5 26. Qc1 Qd5+ 27. Kg1 a5 28. g5 Rff8 29. g6 hxg6 30. Nxg6 Rf6 31. Qc2 Qh5 32. f5 Rxf5 33. Ne5 Rxf1+ 34. Kxf1 Rf8+ 35. Kg1 Qxh4 36. Ng6 Qg3+ 37. Qg2 Rf1+ 0-1

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1998.??.??"]
[Round "?"]
[White "Bensdorp, Laura"]
[Black "Koekoek, Arjen"]
[Result "1/2-1/2"]
[ECO "B46"]
[PlyCount "75"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Nc3 a6 6. a3 Qc7 7. Nb3 Nf6 8. Bd3 Be7 9. 0-0 0-0 10. Be3 b5 11. f3 d6 12. Qe2 Ne5 13. Nd2 Bb7 14. Rab1 d5 15. exd5 Nxd3 16. Qxd3 Nxd5 17. Nxd5 Bxd5 18. c3 Rfd8 19. Qc2 Bd6 20. h3 a5 21. Rbc1 Rac8 22. Rfd1 a4 23. Re1 Bf4 24. Bxf4 Qxf4 25. Nf1 Bc4 26. Ne3 Bb3 27. Qe2 Qg5 28. Qf2 Rd7 29. Re2 Rcd8 30. Rce1 h6 31. Nf1 Rd5 32. Ne3 R5d6 33. Nf1 R8d7 34. Re5 Qd8 35. Rxb5 Rd1 36. Rbe5 Qb8 37. R5e4 Qb5 38. Rxd1 1/2-1/2

[Event "NED-ch U14"]
[Site "Leiden"]
[Date "1998.??.??"]
[Round "?"]
[White "Huistra, Pieter"]
[Black "Koekoek, Arjen"]
[Result "1/2-1/2"]
[ECO "A85"]
[PlyCount "52"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. d4 f5 2. c4 g6 3. Nc3 Bg7 4. Nf3 Nf6 5. e3 0-0 6. Bd3 d6 7. 0-0 Re8 8. Bc2 Nc6 9. Re1 e5 10. dxe5 dxe5 11. Ba4 Bd7 12. e4 f4 13. b3 Nb4 14. Bxd7 Nxd7 15. Bb2 Nb6 16. Qe2 a6 17. Rad1 Qe7 18. Rd2 Rad8 19. Red1 Rxd2 20. Rxd2 c5 21. Ne1 Nc6 22. f3 Nd4 23. Qd1 Rd8 24. Nc2 Qd6 25. Nxd4 cxd4 26. Nd5 Nxd5 1/2-1/2

[Event "NED-ch U14"]
[Site "Leiden"]
[Date "1998.??.??"]
[Round "?"]
[White "Koekoek, Arjen"]
[Black "Broersen, Sjors"]
[Result "1/2-1/2"]
[ECO "C01"]
[PlyCount "80"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 e6 2. d4 d5 3. exd5 exd5 4. Nf3 Bg4 5. Bd3 c6 6. Bf4 Bd6 7. Bxd6 Qxd6 8. 0-0 Nd7 9. Re1+ Ne7 10. Qe2 f6 11. Nbd2 Kd8 12. c4 Ng6 13. c5 Qf8 14. Qe3 Bxf3 15. Qxf3 Qf7 16. Re3 Rf8 17. Rae1 b6 18. b4 b5 19. Qh5 Kc7 20. Qxh7 Nf4 21. Qf5 Nxd3 22. Qxd3 g5 23. Qf5 Rae8 24. Nb3 Rxe3 25. fxe3 Re8 26. Na5 Re6 27. Qg4 Qe7 28. Kf2 Qf7 29. g3 Re4 30. Qf3 Qh7 31. Rh1 g4 32. Qe2 Qf5+ 33. Kg2 Qg5 34. Kf2 Qf5+ 35. Ke1 Re6 36. Kd2 Qg5 37. Nb3 Re4 38. Rf1 f5 39. Rf4 Re6 40. Nc1 Nf6 1/2-1/2

[Event "NED-ch U14"]
[Site "Leiden"]
[Date "1998.??.??"]
[Round "?"]
[White "Koekoek, Arjen"]
[Black "Hummel, Erik Jan"]
[Result "0-1"]
[ECO "C01"]
[PlyCount "104"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 e6 2. d4 d5 3. exd5 exd5 4. c4 c6 5. c5 Bf5 6. Bd3 Bxd3 7. Qxd3 Nf6 8. Nc3 Be7 9. Nf3 0-0 10. 0-0 b6 11. b4 a5 12. Na4 Nbd7 13. Nxb6 Nxb6 14. cxb6 axb4 15. b7 Ra7 16. Ne5 Qc7 17. b8Q Rxb8 18. Bf4 Nh5 19. Bd2 f6 20. Nf3 Rba8 21. Qc2 Ra3 22. Qb2 Nf4 23. Bxb4 Nd3 24. Bxa3 Nxb2 25. Bxb2 c5 26. dxc5 Bxc5 27. Nd4 Qb6 28. Nb3 d4 29. Nxc5 Qxb2 30. Nb3 d3 31. Rfb1 Qe5 32. Rd1 Rb8 33. Rab1 Qe2 34. Ra1 Re8 35. Nd2 f5 36. Nf3 Rc8 37. Rd2 Qe4 38. Rdd1 Rc2 39. Re1 Qb4 40. Rab1 Rb2 41. Rbd1 Qc5 42. Rf1 Qc3 43. h3 d2 44. h4 Rxa2 45. Kh1 Rc2 46. Rg1 g6 47. Kh2 h6 48. Rgf1 Kf7 49. Rg1 Kf6 50. h5 g5 51. Rgf1 g4 52. Ng1 Rc1 0-1

[Event "NED-ch U14"]
[Site "Leiden"]
[Date "1998.??.??"]
[Round "?"]
[White "Koekoek, Arjen"]
[Black "Kodentsov, Grigori"]
[Result "1/2-1/2"]
[ECO "B92"]
[PlyCount "47"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Be2 e5 7. Nb3 Be7 8. 0-0 0-0 9. a4 Be6 10. Be3 Qc7 11. Nd5 Nxd5 12. exd5 Bf5 13. c4 Nd7 14. a5 Bg6 15. Qd2 Rac8 16. Rac1 Qb8 17. Qb4 Nc5 18. Nxc5 dxc5 19. Qc3 Bd6 20. f3 f5 21. Qb3 Bh5 22. Qc2 Bg6 23. Qb3 Bh5 24. Qc2 1/2-1/2

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1998.??.??"]
[Round "?"]
[White "Koekoek, Arjen"]
[Black "Konijn, Bart"]
[Result "1-0"]
[ECO "C47"]
[PlyCount "67"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Nf6 5. Nc3 Bb4 6. Nxc6 bxc6 7. Bd3 0-0 8. 0-0 d5 9. e5 Ng4 10. a3 Bc5 11. h3 Nxe5 12. Bxh7+ Kxh7 13. Qh5+ Kg8 14. Qxe5 Re8 15. Qg3 Bd6 16. Bf4 Qf6 17. Bxd6 cxd6 18. Rfe1 Re5 19. f4 Rxe1+ 20. Rxe1 Bf5 21. Qf2 Rb8 22. g4 Rxb2 23. gxf5 Qxf5 24. Re8+ Kh7 25. Qh4+ Kg6 26. Qg3+ Kf6 27. Ne4+ dxe4 28. Qc3+ Kg6 29. Qxb2 Qxf4 30. Qc3 Qg5+ 31. Kh1 Qd5 32. Qg3+ Kf6 33. Qf4+ Qf5 34. Qxd6+ 1-0

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1998.??.??"]
[Round "?"]
[White "Koekoek, Arjen"]
[Black "Van Dommelen, Martin"]
[Result "1/2-1/2"]
[ECO "C50"]
[PlyCount "43"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. Nc3 Nf6 5. d3 h6 6. h3 d6 7. Na4 Bb6 8. Nxb6 axb6 9. a3 Be6 10. Bb5 0-0 11. Bxc6 bxc6 12. 0-0 Re8 13. Re1 Bd7 14. c3 c5 15. Qc2 Bc6 16. c4 Bb7 17. Be3 Qd7 18. Nh4 Bc8 19. b4 cxb4 20. axb4 Bb7 21. b5 Reb8 22. Qd2 1/2-1/2

[Event "NED-ch U14"]
[Site "Leiden"]
[Date "1998.??.??"]
[Round "?"]
[White "Koekoek, Arjen"]
[Black "Van den Oord, Pieter"]
[Result "1/2-1/2"]
[ECO "B13"]
[PlyCount "51"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c6 2. d4 d5 3. exd5 cxd5 4. Nf3 Bg4 5. b3 Nc6 6. Bb2 e6 7. Be2 Nf6 8. 0-0 Bd6 9. c4 0-0 10. Ne5 Bxe2 11. Qxe2 Qc7 12. Nd2 Nd7 13. Ndf3 Bxe5 14. dxe5 dxc4 15. Qxc4 Nb6 16. Qe4 Qe7 17. a4 Qb4 18. Qc2 Qg4 19. h3 Qg6 20. Qxg6 hxg6 21. Ba3 Rfd8 22. Rfd1 Rd5 23. Rxd5 Nxd5 24. Rc1 Rd8 25. Rd1 Rc8 26. Rc1 1/2-1/2

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1998.??.??"]
[Round "?"]
[White "Koekoek, Arjen"]
[Black "Visschedijk, Gillian"]
[Result "1-0"]
[ECO "C01"]
[PlyCount "53"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 e6 2. d4 d5 3. exd5 exd5 4. Bd3 Bd6 5. Nf3 Ne7 6. 0-0 0-0 7. c4 dxc4 8. Bxc4 Bf5 9. Re1 c6 10. Nc3 Nd7 11. Bg5 h6 12. Bh4 Re8 13. Qb3 Bg6 14. Bxe7 Rxe7 15. Qxb7 Rxe1+ 16. Rxe1 Nb6 17. Bb3 c5 18. dxc5 Bxc5 19. Qc6 Rc8 20. Qxg6 Qd7 21. Ne5 Qd2 22. Qxf7+ Kh8 23. Rb1 Ba3 24. bxa3 Qxc3 25. Ng6+ Kh7 26. Nf8+ Kh8 27. Qg8# 1-0

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1998.??.??"]
[Round "?"]
[White "Koekoek, Arjen"]
[Black "Willemze, Annemieke"]
[Result "1/2-1/2"]
[ECO "B85"]
[PlyCount "69"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 Nc6 6. Be2 a6 7. Be3 e6 8. 0-0 Be7 9. Kh1 0-0 10. f4 Bd7 11. f5 Nxd4 12. Bxd4 Rc8 13. Qd2 e5 14. Bf2 Bc6 15. Bf3 Qc7 16. g4 h6 17. Rg1 Rfd8 18. g5 hxg5 19. Qxg5 Ne8 20. Qh6 Bf8 21. Rg3 f6 22. Rag1 g5 23. Qh3 Rd7 24. Qg2 Rh7 25. Rh3 Rxh3 26. Qxh3 Qh7 27. Qxh7+ Kxh7 28. Bh5 Ng7 29. Bg6+ Kg8 30. Rc1 Be8 31. Bxe8 Rxe8 32. Nd5 Kf7 33. Bb6 Nh5 34. Re1 Nf4 35. c4 1/2-1/2

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1998.??.??"]
[Round "?"]
[White "Konijn, Rob"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B44"]
[PlyCount "64"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Be2 Nf6 6. Bg5 Qa5+ 7. Bd2 Qc7 8. Nxc6 bxc6 9. Nc3 Be7 10. 0-0 0-0 11. Kh1 d5 12. exd5 cxd5 13. Bd3 e5 14. f3 Be6 15. Qe2 Nd7 16. a3 f5 17. Bb5 d4 18. Bxd7 Qxd7 19. Nd1 Rac8 20. Qxe5 Bf6 21. Qe2 Bc4 22. Qf2 Bxf1 23. Qxf1 Rxc2 24. Qd3 Rcc8 25. Nf2 Rfe8 26. Rd1 Qe6 27. Nh3 Qe2 28. Qb3+ Qc4 29. Qxc4+ Rxc4 30. Nf4 Bg5 31. Nh3 Bxd2 32. Rxd2 Re1+ 0-1

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1998.??.??"]
[Round "?"]
[White "Maassen van den Brink, Koen"]
[Black "Koekoek, Arjen"]
[Result "1/2-1/2"]
[ECO "B45"]
[PlyCount "76"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Nc3 Bb4 6. Qd3 a6 7. Nxc6 bxc6 8. Bd2 Nf6 9. e5 Nd5 10. Nxd5 Bxd2+ 11. Qxd2 cxd5 12. 0-0-0 0-0 13. g3 d6 14. exd6 Qxd6 15. Bg2 Rb8 16. Kb1 Qb6 17. b3 a5 18. Rc1 Ba6 19. Bf1 Bb7 20. Bg2 Bc6 21. Rhd1 Qa6 22. Bf1 Bb5 23. Bxb5 Qxb5 24. Qd3 Qb6 25. Rd2 Ra8 26. Qd4 Qb7 27. c4 a4 28. Rd3 Qa6 29. Rc2 axb3 30. Rxb3 Qa4 31. Qb2 dxc4 32. Rb4 Qa5 33. Rcxc4 Rfd8 34. Rc1 h6 35. h4 Qf5+ 36. Qc2 Qa5 37. Qb2 Qf5+ 38. Qc2 Qa5 1/2-1/2

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1998.??.??"]
[Round "?"]
[White "Ondersteijn, Niels"]
[Black "Koekoek, Arjen"]
[Result "1/2-1/2"]
[ECO "B46"]
[PlyCount "45"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Nc3 a6 6. Be3 Bb4 7. a3 Ba5 8. b4 Bc7 9. Be2 Nge7 10. 0-0 0-0 11. f4 Nxd4 12. Bxd4 Nc6 13. Be3 Bb6 14. Bxb6 Qxb6+ 15. Kh1 Qc7 16. Qd3 Ne7 17. e5 f6 18. exf6 Rxf6 19. Qc4 Qxc4 20. Bxc4 b5 21. Bd3 Bb7 22. Be4 Bxe4 23. Nxe4 1/2-1/2

[Event "NED-ch U14"]
[Site "Leiden"]
[Date "1998.??.??"]
[Round "?"]
[White "Ruygrok, Dennis"]
[Black "Koekoek, Arjen"]
[Result "1/2-1/2"]
[ECO "B46"]
[PlyCount "44"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Nc3 a6 6. Be3 Bb4 7. Nxc6 bxc6 8. Bd4 Nf6 9. Qf3 c5 10. Bxf6 Qxf6 11. Qxf6 gxf6 12. Bd3 Bxc3+ 13. bxc3 Bb7 14. 0-0 Ke7 15. Rab1 Bc6 16. Rb6 a5 17. Rfb1 c4 18. Bxc4 Bxe4 19. Bd3 Bc6 20. f3 Rhc8 21. c4 Kd6 22. Kf2 h6 1/2-1/2

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1998.??.??"]
[Round "?"]
[White "Stotyn, Fabian"]
[Black "Koekoek, Arjen"]
[Result "1/2-1/2"]
[ECO "B49"]
[PlyCount "66"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Be3 a6 6. Be2 Nf6 7. Nc3 Bb4 8. Bf3 Qc7 9. 0-0 0-0 10. Nce2 Ne5 11. c3 Bd6 12. Ng3 Nc4 13. Qc1 Nxe3 14. Qxe3 Bf4 15. Qd3 Rb8 16. Nde2 Be5 17. Rad1 b5 18. h3 Bb7 19. Nh5 Rbd8 20. Nxf6+ Bxf6 21. Qd6 Qc4 22. b3 Qc6 23. e5 Qxd6 24. exd6 Bxf3 25. gxf3 Rc8 26. Rd3 Rc6 27. Rc1 Be5 28. f4 Bf6 29. Ng3 g6 30. Ne4 Bg7 31. b4 Rfc8 32. Nc5 Bf8 33. Rcd1 Rd8 1/2-1/2

[Event "NED-ch U14"]
[Site "Leiden"]
[Date "1998.??.??"]
[Round "?"]
[White "Van Deutekom, Yde"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B46"]
[PlyCount "138"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Be3 a6 6. Nc3 Bb4 7. Qd3 Nf6 8. Be2 Ne5 9. Qd1 Nxe4 10. 0-0 Bxc3 11. bxc3 Nxc3 12. Qe1 Nxe2+ 13. Qxe2 Ng6 14. f4 f5 15. Rad1 Qf6 16. Nb3 0-0 17. Bd4 Qf7 18. Rd3 d6 19. Bc3 e5 20. Rxd6 exf4 21. Bd2 Bd7 22. Qf2 Bb5 23. Rd1 Qc4 24. c3 Qe2 25. Qxe2 Bxe2 26. Re1 f3 27. Nd4 Bc4 28. gxf3 Bxa2 29. Rd7 b5 30. Ra1 Bc4 31. Rd6 Rf6 32. Rxf6 gxf6 33. Nxf5 a5 34. Nd4 a4 35. Bc1 Ne5 36. Ba3 Kf7 37. Re1 Re8 38. Kg2 Rg8+ 39. Kh1 Re8 40. Kg2 Nd3 41. Rxe8 Kxe8 42. Nc2 Kd7 43. Kg3 Ke6 44. Nd4+ Kf7 45. Nc2 Ne5 46. Nd4 Nd3 47. Nc2 Kg6 48. Nd4 Kg5 49. Be7 Nc1 50. Bb4 Na2 51. Nc2 Bd3 52. Na3 Nxb4 53. cxb4 Kf5 54. Kf2 Kf4 55. h3 h6 56. Kg2 Ke3 57. Kg3 Kd4 58. Kf4 h5 59. h4 Bc4 60. Kf5 Kc3 61. Nxc4 Kxc4 62. Kxf6 a3 63. Kg5 a2 64. Kxh5 a1Q 65. f4 Qg7 66. f5 Kxb4 67. f6 Qxf6 68. Kg4 Qxh4+ 69. Kxh4 Kc3 0-1

[Event "NED-ch U14"]
[Site "Leiden"]
[Date "1998.??.??"]
[Round "?"]
[White "Van Duijvenbode, Harrie"]
[Black "Koekoek, Arjen"]
[Result "1-0"]
[ECO "B21"]
[PlyCount "39"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 d6 5. Nf3 Nc6 6. Bc4 Bg4 7. Qb3 e6 8. Qxb7 Qc8 9. Ba6 Nce7 10. Nb5 Qxb7 11. Nxd6+ Kd7 12. Bxb7 Rb8 13. Nxf7 Rxb7 14. N3e5+ Kc7 15. Nxg4 h5 16. Nxh8 hxg4 17. Nf7 Ng6 18. 0-0 Nf6 19. Ng5 Kd7 20. b3 1-0

[Event "NED-ch U14"]
[Site "Leiden"]
[Date "1998.??.??"]
[Round "?"]
[White "Visser, Richard"]
[Black "Koekoek, Arjen"]
[Result "1/2-1/2"]
[ECO "B21"]
[PlyCount "38"]
[EventDate "1998.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2002"]
[Source "ChessBase"]
[SourceDate "2001.11.25"]
[SourceVersion "1"]
[SourceVersionDate "2001.11.25"]
[SourceQuality "1"]

1. e4 c5 2. d4 cxd4 3. c3 dxc3 4. Nxc3 e6 5. Nf3 Nc6 6. Bc4 Qc7 7. 0-0 Nf6 8. Qe2 Ng4 9. g3 h5 10. Bf4 e5 11. Be3 Be7 12. Nd5 Qd8 13. Nxe7 Qxe7 14. Nh4 d6 15. f4 Nxe3 16. Qxe3 Be6 17. Bxe6 Qxe6 18. Nf5 0-0-0 19. Nxg7 Qf6 1/2-1/2

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1997.??.??"]
[Round "9"]
[White "Koekoek, Arjen"]
[Black "Benning, Tim"]
[Result "0-1"]
[ECO "C47"]
[PlyCount "46"]
[EventDate "1997.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Nf6 5. Nc3 Bb4 6. Nxc6 bxc6 7. Bd3 d5 8. exd5 cxd5 9. 0-0 0-0 10. Bd2 Bb7 11. a3 Be7 12. Re1 a6 13. Qf3 Rb8 14. b4 c5 15. Qe2 Bd6 16. bxc5 Bxc5 17. Bxa6 Bxa6 18. Qxa6 Ng4 19. Rf1 Qh4 20. Bf4 Bxf2+ 21. Kh1 Nxh2 22. g3 Qh3 23. Rxf2 Nf3+ 0-1

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1997.??.??"]
[Round "5"]
[White "Koekoek, Arjen"]
[Black "De Jong, Bert"]
[Result "1/2-1/2"]
[ECO "B73"]
[PlyCount "60"]
[EventDate "1997.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 g6 6. Be3 Bg7 7. Be2 0-0 8. 0-0 a6 9. Qd2 d6 10. Nxc6 bxc6 11. Bh6 Rb8 12. Bxg7 Kxg7 13. Rab1 c5 14. Rfd1 Qa5 15. Bc4 Bb7 16. Bd5 Nxd5 17. exd5 Bc8 18. b3 Bf5 19. Na4 Qxd2 20. Rxd2 Rfc8 21. Re1 Kf6 22. c4 Re8 23. Nc3 Ra8 24. Rde2 h5 25. Ne4+ Bxe4 26. Rxe4 a5 27. R4e3 a4 28. Rb1 Reb8 29. Kf1 Rb7 30. Ke1 Rab8 1/2-1/2

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1997.??.??"]
[Round "8"]
[White "Koekoek, Arjen"]
[Black "De Jong, Jasper"]
[Result "1-0"]
[ECO "C47"]
[PlyCount "89"]
[EventDate "1997.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Bc5 5. Be3 Bb6 6. Bc4 Nf6 7. Nc3 0-0 8. 0-0 d6 9. Re1 Re8 10. Nxc6 bxc6 11. Bg5 Bb7 12. Na4 h6 13. Nxb6 axb6 14. Bh4 c5 15. f3 Qe7 16. a4 Qe5 17. c3 Bc6 18. Qc2 Ra5 19. b4 Raa8 20. b5 Bd7 21. Rad1 Ra5 22. Bb3 Rea8 23. Bxf6 Qxf6 24. e5 Qg5 25. exd6 cxd6 26. Rxd6 c4 27. Rxd7 cxb3 28. Qxb3 Qf5 29. Rd4 Qc5 30. Kh1 Rc8 31. Rd7 Qxc3 32. Qxf7+ Kh7 33. Qf5+ Kh8 34. Rde7 Rca8 35. Qg4 Rg8 36. Qe6 Rb8 37. Qc6 Qb4 38. R7e4 Qd2 39. Qc1 Qd5 40. f4 Rc8 41. Qe3 Rb8 42. h3 Qd6 43. Re6 Qb4 44. f5 Qxa4 45. Rxh6+ 1-0

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1997.??.??"]
[Round "3"]
[White "Koekoek, Arjen"]
[Black "Veenstra, Petra"]
[Result "1/2-1/2"]
[ECO "C45"]
[PlyCount "70"]
[EventDate "1997.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Bc5 5. Be3 Qf6 6. c3 d6 7. Bc4 Bd7 8. 0-0 Nge7 9. Na3 0-0 10. Nxc6 Bxc6 11. Bxc5 dxc5 12. Re1 Ng6 13. Qh5 Qe5 14. Qxe5 Nxe5 15. f4 Nd7 16. Rad1 Nb6 17. Bd5 Bxd5 18. exd5 Rad8 19. c4 a6 20. Re7 Rc8 21. Rde1 Rfd8 22. b3 Kf8 23. Nb1 Re8 24. Rxe8+ Rxe8 25. Rxe8+ Kxe8 26. Nd2 Ke7 27. Ne4 Nd7 28. Kf2 b6 29. Ng5 Nf6 30. Kf3 h6 31. Nh3 Ne8 32. Nf2 Nd6 33. Nd3 Nf5 34. Ne5 Nd4+ 35. Ke4 a5 1/2-1/2

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1997.??.??"]
[Round "1"]
[White "Koekoek, Arjen"]
[Black "Zoutman, Floris"]
[Result "1-0"]
[ECO "B45"]
[PlyCount "73"]
[EventDate "1997.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 e6 6. a3 Be7 7. Be3 d5 8. exd5 exd5 9. Bb5 Bd7 10. 0-0 a6 11. Ba4 0-0 12. Re1 Re8 13. h3 Rc8 14. Bb3 Nxd4 15. Bxd4 Be6 16. Qf3 Kh8 17. Rad1 Rc7 18. Bxf6 Bxf6 19. Nxd5 Bxd5 20. Rxe8+ Qxe8 21. Qxd5 Re7 22. Qa5 Rd7 23. Rxd7 Qxd7 24. Qc5 Be7 25. Qd5 Qxd5 26. Bxd5 Kg8 27. Bxb7 a5 28. f3 Kf8 29. Kf2 Ke8 30. Ke3 Bg5+ 31. Kd3 Bc1 32. Kc3 Kd7 33. a4 Ke6 34. b4 axb4+ 35. Kxb4 Kd6 36. a5 Kc7 37. Be4 1-0

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1997.??.??"]
[Round "4"]
[White "Lesger, Morrison"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B46"]
[PlyCount "84"]
[EventDate "1997.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Nc3 a6 6. Be2 Bb4 7. 0-0 Nf6 8. Nxc6 bxc6 9. Bg5 Be7 10. e5 Nd5 11. Bxe7 Qxe7 12. Ne4 0-0 13. c4 Nf4 14. c5 a5 15. Bf3 Ba6 16. Re1 Nd3 17. Re3 Nxe5 18. Nd6 Nc4 19. Nxc4 Bxc4 20. Qd4 Ba6 21. Rd1 Rfd8 22. Be2 Bxe2 23. Rxe2 Rab8 24. Qd6 Qxd6 25. Rxd6 Rb7 26. Red2 Rc7 27. a3 Kf8 28. R2d4 Ke7 29. b4 Ra8 30. a4 axb4 31. Rxb4 Ra5 32. Rc4 e5 33. Rd3 Rca7 34. Ra3 Ke6 35. f3 Kd5 36. Rc2 Rxa4 37. Rd3+ Rd4 38. Re3 f6 39. g4 Ra5 40. Rec3 e4 41. fxe4+ Rxe4 42. h3 Raa4 0-1

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1997.??.??"]
[Round "6"]
[White "Muhren, Willem"]
[Black "Koekoek, Arjen"]
[Result "0-1"]
[ECO "B44"]
[PlyCount "200"]
[EventDate "1997.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Nb5 d6 6. N1c3 a6 7. Nd4 Nf6 8. a4 Be7 9. Be3 0-0 10. Bd3 e5 11. Nde2 Ng4 12. Nd5 Nxe3 13. Nxe3 Be6 14. 0-0 Qb6 15. b3 Bg5 16. Nd5 Bxd5 17. exd5 Ne7 18. c4 f5 19. Kh1 Bf6 20. Rb1 e4 21. Bc2 Be5 22. Qd2 Ng6 23. a5 Qc5 24. Nc3 Bf4 25. Qe2 Qxa5 26. Na4 b5 27. Nb2 Qb6 28. g4 fxg4 29. Qxe4 Rae8 30. Qg2 Ne5 31. Nd3 h5 32. Nxe5 Rxe5 33. Rbe1 Qd4 34. Rxe5 Qxe5 35. f3 g3 36. hxg3 Bxg3 37. Be4 h4 38. Qh3 bxc4 39. bxc4 Re8 40. Bg6 Rf8 41. Qe6+ Kh8 42. f4 Qb2 43. Qh3 Qe2 44. f5 Qxc4 45. Qg2 a5 46. Qf3 Kg8 47. Qg2 a4 48. Ra1 a3 49. Qa2 Qxa2 50. Rxa2 Ra8 51. Bh5 Kf8 52. Kg2 Ke7 53. Kf3 Kf6 54. Kg4 Ra4+ 55. Kf3 Kxf5 56. Be8 Ra5 57. Bf7 g5 58. Be6+ Ke5 59. Ke3 Bf4+ 60. Kd3 Bc1 61. Rf2 Bf4 62. Ra2 Ra4 63. Re2+ Kf6 64. Ra2 Bc1 65. Rf2+ Rf4 66. Rg2 Bb2 67. Kc2 Kg6 68. Bg4 Rd4 69. Be6 Kh5 70. Bf7+ Kh6 71. Be6 Rc4+ 72. Kb3 Rc3+ 73. Ka2 Rg3 74. Rh2 Kh5 75. Rf2 h3 76. Rf7 Kg6 77. Rf2 g4 78. Bf5+ Kg5 79. Be4 Re3 80. Bh1 g3 81. Rf8 Bc1 82. Rg8+ Kf4 83. Rf8+ Ke5 84. Re8+ Kd4 85. Rg8 g2 86. Bxg2 hxg2 87. Rxg2 Kxd5 88. Rg5+ Kc4 89. Ra5 d5 90. Ra8 Bb2 91. Rc8+ Kd3 92. Rg8 d4 93. Rg2 Re2 94. Rg8 Kd2 95. Rc8 d3 96. Rc6 Ke1 97. Rg6 d2 98. Rg1+ Kf2 99. Rg8 d1R 100. Rf8+ Ke1 0-1

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1997.??.??"]
[Round "2"]
[White "Schrevens, Birger"]
[Black "Koekoek, Arjen"]
[Result "1/2-1/2"]
[ECO "B46"]
[PlyCount "100"]
[EventDate "1997.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Be3 a6 6. Nc3 Nf6 7. Be2 Bb4 8. f3 0-0 9. 0-0 Bc5 10. Qd2 Nxd4 11. Bxd4 Bxd4+ 12. Qxd4 Qc7 13. e5 Nd5 14. Nxd5 exd5 15. c3 d6 16. exd6 Qxd6 17. Rad1 Be6 18. Rfe1 Rad8 19. Bc4 Qc7 20. Bb3 Rd7 21. Re5 Rfd8 22. f4 g6 23. h3 Rd6 24. g4 f6 25. Re2 Qb6 26. Qxb6 Rxb6 27. Red2 Rbd6 28. Rd4 R6d7 29. Bc2 g5 30. f5 Bf7 31. Bb3 b5 32. a4 bxa4 33. Bxa4 Rb7 34. b3 Rc8 35. R4d3 Rbc7 36. Rc1 Rc5 37. Kf2 h5 38. Ke2 h4 39. Kd2 Kf8 40. Re1 a5 41. Bd7 R8c7 42. Be6 Bxe6 43. Rxe6 Kf7 44. Kc2 Rd7 45. Rd1 Re7 46. Rd3 Rd7 47. Kb2 Rb5 48. c4 Rc5 49. Kc3 Rd8 50. Rd4 Rdc8 1/2-1/2

[Event "Hengelo U14 op"]
[Site "Hengelo"]
[Date "1997.??.??"]
[Round "7"]
[White "Van Beek, Guido"]
[Black "Koekoek, Arjen"]
[Result "1-0"]
[ECO "B46"]
[PlyCount "106"]
[EventDate "1997.??.??"]
[EventType "swiss"]
[EventRounds "9"]
[EventCountry "NED"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e6 5. Nc3 a6 6. Nxc6 bxc6 7. Bd3 Qc7 8. f4 d5 9. 0-0 Ne7 10. Kh1 dxe4 11. Nxe4 f5 12. Ng5 h6 13. Nh3 g6 14. Qf3 Bg7 15. c3 Kf7 16. Be3 Bb7 17. Qf2 Nd5 18. Bc5 Rhe8 19. c4 Nf6 20. Rae1 Ng4 21. Qc2 Bc8 22. Be2 Nf6 23. Bf3 Kg8 24. Rd1 Bb7 25. Rfe1 Bf8 26. Bd4 Bg7 27. Be5 Qc8 28. Qc3 Rf8 29. Rd2 Kh7 30. Red1 Rf7 31. b4 c5 32. Bxb7 Qxb7 33. bxc5 Ne4 34. Qd4 Nxd2 35. Rxd2 Bxe5 36. Qxe5 Qb1+ 37. Ng1 Qe4 38. Re2 Qxc4 39. Qd6 Re8 40. c6 Rfe7 41. Re5 Qa4 42. Rc5 Kg7 43. c7 Qd7 44. Qxd7 Rxd7 45. c8Q Rxc8 46. Rxc8 Kf6 47. Rc6 a5 48. Rc5 Rd4 49. g3 Ra4 50. Rc2 g5 51. Ne2 gxf4 52. gxf4 Re4 53. Kg2 e5 1-0

