[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.02"]
[Round "15"]
[White "De Leon, Otto"]
[Black "Camaton Borbor, Carlos"]
[Result "0-1"]
[ECO "B44"]
[BlackElo "2240"]
[PlyCount "66"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nf6 5. Bd3 Nc6 6. Be3 d5 7. Nd2 e5 8. Nxc6 bxc6 9. exd5 cxd5 10. Bg5 Rb8 11. Qe2 Bd6 12. Bb5+ Kf8 13. b3 Qa5 14. Bxf6 gxf6 15. Ba4 Ba6 16. Qe3 Rg8 17. Qh6+ Ke7 18. Qh3 Bb4 19. Rd1 Bc8 20. Qxh7 Ba6 21. Qh3 Rgd8 22. Qe3 Rbc8 23. a3 Bc3 24. Qxa7+ Kf8 25. Qe3 d4 26. Qh6+ Ke7 27. Qh5 d3 28. 0-0 dxc2 29. Ne4 cxd1Q 30. Rxd1 Rxd1+ 31. Qxd1 Bd4 32. h3 f5 33. Ng3 Bxf2+ 0-1

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "7"]
[White "Anelli, Antonio"]
[Black "De Leon, Otto"]
[Result "1-0"]
[ECO "A43"]
[WhiteElo "2290"]
[PlyCount "49"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. d4 c5 2. d5 e6 3. e4 exd5 4. exd5 d6 5. Nc3 a6 6. a4 b6 7. Nf3 Bg4 8. Be2 Nf6 9. 0-0 Be7 10. Bf4 0-0 11. Nd2 Bf5 12. Nc4 Qc7 13. Bd3 Bxd3 14. Qxd3 Rd8 15. Rfe1 h6 16. Qf3 Kf8 17. Re2 g5 18. Bg3 Kg7 19. Ne3 Bf8 20. Nf5+ Kh7 21. Nxh6 Kg7 22. Nf5+ Kg8 23. Ne4 Nxe4 24. Rxe4 Nd7 25. Qh5 1-0

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "10"]
[White "Bademian Orchanian, Jose"]
[Black "De Leon, Otto"]
[Result "1-0"]
[ECO "B08"]
[WhiteElo "2235"]
[PlyCount "49"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. e4 g6 2. d4 Bg7 3. Nc3 d6 4. Bc4 Nf6 5. Nf3 0-0 6. Qe2 c6 7. e5 dxe5 8. dxe5 Nd5 9. Bd2 Bg4 10. 0-0-0 e6 11. Rhe1 Nd7 12. Bxd5 cxd5 13. Bf4 a6 14. h3 Bxf3 15. Qxf3 Qa5 16. Kb1 Rac8 17. h4 Rc4 18. h5 b5 19. hxg6 fxg6 20. Nxd5 Nc5 21. Ne7+ Kh8 22. Rh1 Rcxf4 23. Nxg6+ Kg8 24. Ne7+ Kh8 25. Rxh7+ 1-0

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "3"]
[White "Berry, Jonathan"]
[Black "De Leon, Otto"]
[Result "0-1"]
[ECO "E97"]
[WhiteElo "2315"]
[PlyCount "73"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. Nf3 Nf6 2. c4 g6 3. Nc3 Bg7 4. d4 d6 5. e4 0-0 6. Be2 Nc6 7. 0-0 e5 8. d5 Ne7 9. Bd2 Nh5 10. g3 Bh3 11. Re1 Bg4 12. h3 Bxf3 13. Bxf3 Nf6 14. Rc1 h6 15. b4 Nd7 16. c5 a6 17. Na4 f5 18. Bc3 Nf6 19. exf5 gxf5 20. Bg2 b5 21. cxb6 cxb6 22. Qb3 Kh8 23. Nb2 Rc8 24. Nd3 Nd7 25. f4 Ng6 26. Bd2 Ne7 27. Rxc8 Qxc8 28. fxe5 dxe5 29. d6 Ng6 30. h4 e4 31. h5 Nge5 32. Nf4 Rf6 33. Qd5 Qb8 34. Rc1 Qxd6 35. Rc8+ Nf8 36. Bc3 Qxd5 37. Nxd5 0-1

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "12"]
[White "Chavez, Romelio"]
[Black "De Leon, Otto"]
[Result "1-0"]
[ECO "B07"]
[PlyCount "97"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. e4 g6 2. d4 Bg7 3. f4 d6 4. Nf3 Nf6 5. Bd3 0-0 6. e5 Nd5 7. 0-0 Bg4 8. h3 Bc8 9. a3 e6 10. c4 Ne7 11. Nc3 c5 12. Ne4 dxe5 13. dxe5 Nd7 14. Be3 Qc7 15. Qe2 b6 16. Nd6 Bb7 17. Nxb7 Qxb7 18. Ng5 Rad8 19. g4 Nc6 20. Ne4 f5 21. Nd6 Qb8 22. gxf5 gxf5 23. Bc2 Ne7 24. Qg2 Nc8 25. Nb7 Rde8 26. Rad1 Qc7 27. Ba4 Re7 28. Nd6 a6 29. Qg5 Nb8 30. Rf2 Kh8 31. Rg2 Na7 32. Qh5 Nbc6 33. Kh2 Nc8 34. b4 cxb4 35. axb4 N8a7 36. b5 axb5 37. cxb5 Nd8 38. Rc2 Qb8 39. Bb3 Nb7 40. Bxb6 Nxd6 41. exd6 Rd7 42. Bc7 Qxb5 43. Bxe6 Qa4 44. Rf2 Qb5 45. Rd5 Qc6 46. Bxf5 Bf6 47. Bxd7 Qxd7 48. Qf5 Qc6 49. Rc2 1-0

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "13"]
[White "De Leon, Otto"]
[Black "Denker, Arnold Sheldon"]
[Result "1/2-1/2"]
[ECO "B44"]
[BlackElo "2335"]
[PlyCount "45"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Be3 Nf6 6. Bd3 d5 7. exd5 Nxd5 8. Nxc6 bxc6 9. Bd2 Rb8 10. b3 Qf6 11. c3 Bd6 12. 0-0 0-0 13. Qc1 Nf4 14. Bxf4 Bxf4 15. Qc2 g6 16. Nd2 c5 17. Rad1 Rd8 18. Be4 Ba6 19. Rfe1 Be5 20. c4 Bc3 21. Rf1 Bd4 22. Nf3 e5 23. Rfe1 1/2-1/2

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "9"]
[White "De Leon, Otto"]
[Black "Donoso Velasco, Pedro H"]
[Result "0-1"]
[ECO "B44"]
[BlackElo "2400"]
[PlyCount "72"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nb5 d6 6. Be3 Nf6 7. Bd3 a6 8. Nd4 Be7 9. Nxc6 bxc6 10. 0-0 e5 11. c4 0-0 12. Nc3 Be6 13. Qe2 a5 14. Rad1 Qc7 15. h3 g6 16. Rd2 Nh5 17. b3 Nf4 18. Qf3 Nxd3 19. Rxd3 f5 20. Qe2 a4 21. f3 f4 22. Bf2 axb3 23. axb3 Rfb8 24. Qc2 g5 25. Rfd1 h5 26. Ne2 g4 27. hxg4 hxg4 28. g3 gxf3 29. Rxf3 Bg4 30. Rfd3 f3 31. Nc1 c5 32. Qd2 Kg7 33. Qe3 Qd8 34. Rd5 Qh8 35. Kf1 Qh1+ 36. Bg1 f2 0-1

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "6"]
[White "De Leon, Otto"]
[Black "Grimaldi, Rene A"]
[Result "1-0"]
[ECO "C45"]
[PlyCount "74"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. d4 exd4 4. Nxd4 Bc5 5. Nb3 Bb6 6. Bd3 Qf6 7. 0-0 Nge7 8. Nc3 d6 9. Kh1 Ne5 10. Be2 Qh4 11. Nd4 Bd7 12. Be3 0-0-0 13. Qd2 f6 14. a4 a6 15. Nf3 Nxf3 16. Bxf3 Bxe3 17. Qxe3 g5 18. b4 Bg4 19. Bxg4+ Qxg4 20. b5 axb5 21. axb5 Kd7 22. Rfe1 Rhe8 23. Qd3 Qe6 24. Ne2 Ra8 25. Rad1 h5 26. Nd4 Qe5 27. Nf3 Qc5 28. e5 Ra3 29. Qh7 Rxf3 30. exd6 cxd6 31. gxf3 Qxf2 32. Qe4 Kc7 33. Re2 Qc5 34. c4 f5 35. Qe6 g4 36. fxg4 fxg4 37. Qf7 Kd8 1-0

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "11"]
[White "De Leon, Otto"]
[Black "Hook, William"]
[Result "1-0"]
[ECO "C18"]
[BlackElo "2250"]
[PlyCount "81"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. e4 e6 2. d4 d5 3. Nc3 Bb4 4. e5 c5 5. a3 Bxc3+ 6. bxc3 Qa5 7. Bd2 Qa4 8. Qg4 Kf8 9. Qd1 b6 10. f4 Ne7 11. Nf3 h5 12. Bd3 Ba6 13. 0-0 Bxd3 14. cxd3 Qxd1 15. Raxd1 Na6 16. dxc5 Nxc5 17. Be3 Na4 18. c4 Nf5 19. Bf2 Rc8 20. Rc1 dxc4 21. dxc4 Ke7 22. h3 Rhd8 23. g4 hxg4 24. hxg4 Nh6 25. Bh4+ f6 26. g5 Ng8 27. gxf6+ gxf6 28. exf6+ Nxf6 29. Ne5 Rg8+ 30. Kf2 Nc5 31. Kf3 Rcf8 32. Rcd1 Ke8 33. Rd6 Rg7 34. Rc6 Kd8 35. Rd1+ Ncd7 36. Ng4 Rxg4 37. Bxf6+ Rxf6 38. Kxg4 Rf7 39. Rxe6 Kc7 40. Rde1 Rg7+ 41. Kf3 1-0

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "4"]
[White "De Leon, Otto"]
[Black "Van Riemsdijk, Herman Claudius"]
[Result "0-1"]
[ECO "A07"]
[BlackElo "2385"]
[PlyCount "80"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. Nf3 g6 2. g3 Bg7 3. Bg2 e5 4. d3 d5 5. 0-0 Ne7 6. e4 0-0 7. Nc3 c6 8. Kh1 Na6 9. Re1 Qc7 10. a3 h6 11. Ng1 Rd8 12. Qe2 d4 13. Nd1 c5 14. f4 Be6 15. fxe5 c4 16. Nf3 cxd3 17. cxd3 Nc5 18. Nf2 Nb3 19. Rb1 Rac8 20. Bd2 Nc6 21. Bh3 Qd7 22. Bxe6 Qxe6 23. Red1 Rd7 24. Kg2 g5 25. h3 Nxe5 26. Ne1 a5 27. g4 Ng6 28. Nh1 Be5 29. Ng3 Bxg3 30. Kxg3 Qe5+ 31. Kg2 Nh4+ 32. Kh1 Rd6 33. Qh2 Qxh2+ 34. Kxh2 Rf6 35. Kg3 Rf1 36. Bc1 Nf3 37. Bxg5 Nxg5 38. h4 Ne6 39. Kg2 Rf4 40. Kg3 h5 0-1

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "2"]
[White "De Leon, Otto"]
[Black "Zarco Castillo, Jose"]
[Result "1/2-1/2"]
[ECO "B06"]
[PlyCount "132"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. e4 g6 2. d4 Bg7 3. f4 d6 4. Be2 c5 5. c3 cxd4 6. cxd4 Qb6 7. e5 dxe5 8. dxe5 Nh6 9. Nc3 0-0 10. Nd5 Qd8 11. Nf3 Be6 12. Ne3 Qa5+ 13. Qd2 Qb6 14. Qd4 Qc7 15. 0-0 Nc6 16. Qc5 Rab8 17. Ng5 Bf5 18. Rd1 Qc8 19. Qa3 Rd8 20. Bd2 Nd4 21. Re1 f6 22. exf6 exf6 23. Nxf5 gxf5 24. Nh3 Nc2 25. Qb3+ Kh8 26. Bc3 Nxa1 27. Rxa1 Re8 28. Bf3 b6 29. g3 Qc7 30. Nf2 Re3 31. Kg2 Rbe8 32. Qd5 Rd8 33. Qb3 Rde8 34. Qd5 Qf7 35. Qc6 Qe6 36. Qb7 Ng4 37. h3 Nxf2 38. Kxf2 h6 39. a4 Bf8 40. Bd5 Re2+ 41. Kf1 Qd6 42. Qf7 Bg7 43. Be5 R2xe5 44. fxe5 Qxe5 45. Bf3 Qe3 46. Qh5 Re5 47. h4 f4 48. Qg4 fxg3 49. Qxg3 f5 50. Rd1 Bf6 51. Rd6 Re8 52. Qf2 Qxf2+ 53. Kxf2 Bxh4+ 54. Kg2 Bg5 55. Bh5 Rc8 56. Bd1 Rc7 57. Rd5 Rc1 58. b4 Kg7 59. Bh5 Kf6 60. Rd7 Rc4 61. Rxa7 Rxb4 62. a5 bxa5 63. Rxa5 Be3 64. Be2 Bb6 65. Rb5 Rxb5 66. Bxb5 Kg5 1/2-1/2

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "1"]
[White "Escondrillas, Carlos"]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "A34"]
[WhiteElo "2265"]
[PlyCount "43"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. c4 Nf6 2. g3 g6 3. Bg2 Bg7 4. Nc3 c5 5. e3 a6 6. d4 Qc7 7. b3 d6 8. Nge2 Nbd7 9. 0-0 Rb8 10. a4 b6 11. d5 0-0 12. Bb2 Ne8 13. Qd2 Ndf6 14. Ra2 Bd7 15. Rfa1 Qc8 16. Nd1 Nc7 17. Bc3 Bh3 18. f3 Bxg2 19. Kxg2 Qd7 20. Nf2 Rb7 21. e4 Rfb8 22. Nd3 1/2-1/2

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "5"]
[White "Gamarra Caceres, Carlos"]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "C41"]
[PlyCount "88"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 d6 3. d4 exd4 4. Qxd4 Nf6 5. Nc3 Be7 6. Bg5 0-0 7. 0-0-0 Nc6 8. Qd2 Be6 9. Nd4 Nxd4 10. Qxd4 Nd7 11. Bf4 Bg5 12. g3 Bf6 13. Qd2 Nb6 14. Nd5 Bg4 15. Be2 Bxe2 16. Qxe2 Nxd5 17. Rxd5 Qe7 18. Rhd1 Rad8 19. Qd3 Rfe8 20. f3 Qf8 21. c4 b6 22. Kc2 Rb8 23. g4 h6 24. Rg1 g5 25. Rf5 Qg7 26. Bc1 Re5 27. h4 Rbe8 28. hxg5 hxg5 29. Be3 Kf8 30. b3 Qh6 31. Qd2 Bd8 32. Qg2 Bf6 33. Rh1 Qg7 34. Rh5 Ke7 35. Qh3 Rxf5 36. gxf5 Rg8 37. Qg4 Ke8 38. Kd3 Kd8 39. Rh1 Bb2 40. Ke2 f6 41. Qh5 Qe7 42. Qh7 Qe8 43. Qh5 Qf8 44. a4 Kc8 1/2-1/2

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "14"]
[White "Garcia, Gildardo"]
[Black "De Leon, Otto"]
[Result "1-0"]
[ECO "B01"]
[WhiteElo "2340"]
[PlyCount "91"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. e4 d5 2. exd5 Qxd5 3. Nc3 Qa5 4. d4 Nf6 5. Nf3 Bg4 6. h3 Bxf3 7. Qxf3 c6 8. Bd2 Qd8 9. 0-0-0 e6 10. g4 Be7 11. Kb1 Nbd7 12. g5 Nd5 13. Ne4 b5 14. h4 a5 15. Bh3 Qb6 16. Rhe1 b4 17. h5 g6 18. Qg3 a4 19. Nd6+ Bxd6 20. Qxd6 0-0-0 21. Bg2 Nb8 22. Qe5 Nd7 23. Qg7 Rdf8 24. Bxd5 cxd5 25. Bf4 Kb7 26. Re3 Rhg8 27. Qh6 Qc6 28. Rf3 Rc8 29. Rc1 Rcf8 30. hxg6 hxg6 31. Qh2 Rh8 32. Qg3 Rc8 33. Bd2 Rh7 34. Rf4 Nb6 35. Qf3 Qc7 36. Bxb4 Rh3 37. Qxh3 Qxf4 38. Qe3 Qf5 39. b3 axb3 40. axb3 Nd7 41. Kb2 Nb6 42. Qd2 Rh8 43. Bc5 Kc6 44. Bxb6 Kxb6 45. Qb4+ Kc7 46. Qc5+ 1-0

[Event "Pan American-ch 2nd"]
[Site "Santa Cruz"]
[Date "1977.11.??"]
[Round "8"]
[White "Pesantes Carbajal, Carlos"]
[Black "De Leon, Otto"]
[Result "0-1"]
[ECO "E92"]
[WhiteElo "2290"]
[PlyCount "146"]
[EventDate "1977.11.15"]
[EventType "tourn"]
[EventRounds "15"]
[EventCountry "BOL"]
[SourceTitle "EXT 2022"]
[Source "ChessBase"]
[SourceDate "2021.10.06"]
[SourceVersion "1"]
[SourceVersionDate "2021.10.06"]
[SourceQuality "1"]

1. d4 Nf6 2. c4 g6 3. Nc3 Bg7 4. e4 d6 5. Nf3 0-0 6. Be2 e5 7. d5 Nh5 8. g3 Nd7 9. Nd2 Ndf6 10. b4 Bh6 11. Nf1 Bxc1 12. Rxc1 a5 13. a3 axb4 14. axb4 Bd7 15. Ne3 Ra3 16. 0-0 Ng7 17. c5 Qe7 18. Nc4 Ra7 19. Qd3 Rfa8 20. cxd6 cxd6 21. Nb6 Rb8 22. Qe3 Ra3 23. Ra1 Rb3 24. Rfb1 Rxb1+ 25. Nxb1 Nfe8 26. Ra7 Nc7 27. Na3 f5 28. f3 fxe4 29. fxe4 Bh3 30. Qh6 Nh5 31. Nc2 Qf7 32. Ra1 Rf8 33. Qe3 Nf6 34. Qf3 Nxe4 35. Qxf7+ Rxf7 36. Ne3 Nc3 37. Bf1 Bxf1 38. Rxf1 Na6 39. Nec4 Rxf1+ 40. Kxf1 Nb5 41. Nc8 Nxb4 42. N4xd6 Nxd6 43. Nxd6 Nxd5 44. Nxb7 Kf7 45. Ke2 Ke6 46. Kf3 Nf6 47. h3 Kd5 48. Nd8 Ne4 49. h4 Nd6 50. g4 h6 51. h5 g5 52. Ke3 e4 53. Kf2 Kd4 54. Ke2 Ke5 55. Ke3 Nc4+ 56. Kf2 Kf4 57. Nf7 Kxg4 58. Nxh6+ Kxh5 59. Nf5 Kg4 60. Nd4 Nd6 61. Ne2 Nf5 62. Nc3 Kf4 63. Ne2+ Ke5 64. Kg2 g4 65. Kf1 e3 66. Nc3 Kf4 67. Kg2 Nh4+ 68. Kf1 Kf3 69. Ne2 Nf5 70. Ng1+ Ke4 71. Ne2 Nd4 72. Ng1 Kf4 73. Kg2 e2 0-1

[Event "Salvador int 1st"]
[Site "San Salvador"]
[Date "1974.??.??"]
[Round "2"]
[White "De Leon, Otto"]
[Black "Bronstein, David Ionovich"]
[Result "0-1"]
[ECO "A05"]
[PlyCount "62"]
[EventDate "1974.??.??"]
[EventType "tourn"]
[EventRounds "5"]
[EventCountry "ESA"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. Nf3 Nf6 2. e3 g6 3. b3 Bg7 4. Bb2 0-0 5. Be2 b6 6. d3 c5 7. Nbd2 Nc6 8. Nf1 Bb7 9. Ng3 Qc7 10. 0-0 d5 11. Nd2 Rad8 12. Bf3 e5 13. e4 Nd4 14. Re1 Rfe8 15. Ngf1 Nxf3+ 16. gxf3 Nh5 17. Ng3 Nf4 18. Bc1 Qd7 19. Kh1 dxe4 20. fxe4 Qd4 21. Rb1 Qxf2 22. Rg1 f5 23. Qe1 Nh3 24. Qxf2 Nxf2+ 25. Kg2 Ng4 26. Kh3 Bc8 27. exf5 gxf5 28. Nh5 Re6 29. Nf3 Rg6 30. Kh4 f4 31. h3 Nh2 0-1

[Event "Salvador int 1st"]
[Site "San Salvador"]
[Date "1974.??.??"]
[Round "5"]
[White "De Leon, Otto"]
[Black "Salas, Narciso"]
[Result "1/2-1/2"]
[ECO "C14"]
[PlyCount "97"]
[EventDate "1974.??.??"]
[EventType "tourn"]
[EventRounds "5"]
[EventCountry "ESA"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 e6 2. d4 d5 3. Nc3 Nf6 4. Bg5 Be7 5. e5 Nfd7 6. Bxe7 Qxe7 7. f4 a6 8. Nf3 c5 9. a3 Nc6 10. Bd3 cxd4 11. Ne2 f6 12. Nexd4 Nxd4 13. Nxd4 fxe5 14. fxe5 Nxe5 15. Qh5+ Nf7 16. 0-0 g6 17. Qd1 e5 18. Nb3 Be6 19. c3 0-0 20. Qe2 Qd6 21. Kh1 e4 22. Nd4 Ne5 23. Bc2 Ng4 24. g3 Ne5 25. Nxe6 Qxe6 26. Bb3 Nc4 27. Bxc4 dxc4 28. Rxf8+ Rxf8 29. Re1 b5 30. Kg2 Rd8 31. h4 e3 32. Qxe3 Qxe3 33. Rxe3 Rd2+ 34. Kf3 Rxb2 35. Re8+ Kf7 36. Ra8 Rb3 37. Rxa6 Rxc3+ 38. Kf4 h5 39. g4 hxg4 40. Kxg4 Rd3 41. Ra5 Rd5 42. a4 Rd4+ 43. Kg5 bxa4 44. Ra7+ Ke6 45. Rxa4 Ke5 46. Ra5+ Ke6 47. Ra4 Ke5 48. Ra5+ Ke6 49. Ra4 1/2-1/2

[Event "Salvador int 1st"]
[Site "San Salvador"]
[Date "1974.??.??"]
[Round "4"]
[White "Infante Meyer, Salvador"]
[Black "De Leon, Otto"]
[Result "1-0"]
[ECO "C41"]
[PlyCount "79"]
[EventDate "1974.??.??"]
[EventType "tourn"]
[EventRounds "5"]
[EventCountry "ESA"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 d6 3. d4 Nd7 4. Bc4 c6 5. c3 Be7 6. 0-0 Ngf6 7. Qe2 0-0 8. dxe5 dxe5 9. Rd1 Qc7 10. h3 Nc5 11. Nbd2 h6 12. b4 Na4 13. Qe3 a5 14. a3 Nb6 15. Ba2 Rd8 16. Rb1 Be6 17. Bxe6 fxe6 18. Bb2 Ne8 19. c4 Bf6 20. c5 Na4 21. Ba1 axb4 22. axb4 b5 23. Qb3 Kf7 24. Nf1 g6 25. Ne3 h5 26. Rxd8 Rxd8 27. Rd1 Rxd1+ 28. Qxd1 Ke7 29. h4 Ng7 30. Kf1 Ne8 31. Ke2 Ng7 32. Nc2 Ne8 33. Nce1 Qa7 34. Nd3 Qd7 35. Ndxe5 Qxd1+ 36. Kxd1 Kd8 37. Nxc6+ Kc7 38. e5 Kxc6 39. exf6 Nxf6 40. Bxf6 1-0

[Event "Salvador int 1st"]
[Site "San Salvador"]
[Date "1974.??.??"]
[Round "3"]
[White "Montero, Fernando"]
[Black "De Leon, Otto"]
[Result "1-0"]
[ECO "C26"]
[PlyCount "105"]
[EventDate "1974.??.??"]
[EventType "tourn"]
[EventRounds "5"]
[EventCountry "ESA"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 e5 2. Nc3 Bc5 3. g3 Nc6 4. Bg2 Nf6 5. Nf3 0-0 6. 0-0 d6 7. d3 a6 8. h3 h6 9. Qe2 Be6 10. Kh2 Qd7 11. Be3 Rae8 12. Qd2 Kh7 13. Ne2 Ng8 14. g4 g6 15. Ng3 Qe7 16. c3 Bxe3 17. fxe3 Rd8 18. d4 Bc8 19. Rf2 Kg7 20. Raf1 f6 21. d5 Nb8 22. Qc2 Rf7 23. Nh4 b6 24. Qe2 Rdf8 25. Bh1 a5 26. Rg1 Kh7 27. Ng2 g5 28. Rgf1 Qe8 29. Ne1 Qa4 30. b3 Qa3 31. Bf3 a4 32. Qb2 Qxb2 33. Rxb2 axb3 34. axb3 Ba6 35. Be2 Bxe2 36. Rxe2 Nd7 37. Ra2 Rb8 38. b4 Rff8 39. Nd3 Kg6 40. Rfa1 Rfc8 41. Nf5 b5 42. Ra7 Nb6 43. Nb2 h5 44. Kg3 h4+ 45. Kf3 Na8 46. c4 Re8 47. cxb5 Nh6 48. b6 Nxf5 49. exf5+ Kf7 50. bxc7 Rbc8 51. Rxa8 Rxa8 52. Rxa8 Rxa8 53. b5 1-0

[Event "Salvador int 1st"]
[Site "San Salvador"]
[Date "1974.??.??"]
[Round "1"]
[White "Vaglio Munoz, Jaime"]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "E81"]
[PlyCount "97"]
[EventDate "1974.??.??"]
[EventType "tourn"]
[EventRounds "5"]
[EventCountry "ESA"]
[SourceTitle "EXT 2001"]
[Source "ChessBase"]
[SourceDate "2000.11.22"]
[SourceVersion "1"]
[SourceVersionDate "2000.11.22"]
[SourceQuality "1"]

1. e4 d6 2. d4 Nf6 3. f3 g6 4. c4 Bg7 5. Nc3 c6 6. Be3 0-0 7. Qd2 a6 8. Nge2 b5 9. g4 e5 10. d5 b4 11. Nd1 Bxg4 12. Bg2 Bc8 13. Ng3 c5 14. h4 h5 15. Bg5 Qc7 16. Nf2 Ra7 17. Bh3 Re8 18. Rg1 Kf8 19. Bh6 Bxh6 20. Qxh6+ Ke7 21. Qg5 Bxh3 22. Nxh3 Nbd7 23. Qd2 Kd8 24. Ng5 Nb6 25. b3 a5 26. Kf2 a4 27. Qb2 a3 28. Qd2 Qe7 29. Ke2 Nbd7 30. Kd3 Nf8 31. Ne2 N6h7 32. Nxh7 Nxh7 33. Rh1 Qf6 34. Raf1 Rae7 35. Qe3 Qg7 36. Rfg1 Kc7 37. Rg2 Qf6 38. Rg3 Rh8 39. Kc2 Rhe8 40. Kd3 Kd7 41. Kc2 Rh8 42. Nc1 Rhe8 43. Nd3 Kd8 44. Rh2 Rc7 45. Rg1 Qe7 46. Rh3 Nf8 47. Rg5 f6 48. Rg1 Qf7 49. Rh2 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "19"]
[White "Caro, Alberto Napoleon"]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "B09"]
[PlyCount "16"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 d6 2. d4 g6 3. f4 Bg7 4. Nf3 Nf6 5. Nc3 0-0 6. Be3 c6 7. Qd2 b5 8. a3 Bb7 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "8"]
[White "Chan, H."]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "A24"]
[PlyCount "63"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. c4 Nf6 2. Nc3 g6 3. g3 Bg7 4. Bg2 d6 5. d3 c6 6. e4 e5 7. Nge2 0-0 8. 0-0 Na6 9. h3 Ne8 10. Be3 Be6 11. b3 Qd7 12. Kh2 f5 13. Qd2 Nf6 14. Rad1 c5 15. Nd5 Nh5 16. exf5 gxf5 17. f4 Rae8 18. Nec3 b6 19. a3 Nb8 20. Qf2 Nc6 21. b4 Nd4 22. Bxd4 cxd4 23. Ne2 Kh8 24. Bf3 Nf6 25. Nxf6 Bxf6 26. Qg2 Rc8 27. b5 Rg8 28. Bd5 Qf7 29. Bxe6 Qxe6 30. fxe5 Bxe5 31. Nf4 Qh6 32. Rf3 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "2"]
[White "Cuellar Gacharna, Miguel"]
[Black "De Leon, Otto"]
[Result "1-0"]
[ECO "E91"]
[PlyCount "127"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. c4 Nf6 2. d4 g6 3. Nc3 Bg7 4. e4 d6 5. Be2 c6 6. Nf3 0-0 7. 0-0 Qc7 8. h3 e5 9. Be3 Nh5 10. Re1 Qe7 11. Bf1 Na6 12. g3 Nc7 13. Bg2 Nf6 14. Qc2 Nfe8 15. b4 b6 16. Rad1 Bb7 17. Bg5 Qe6 18. Qd3 h6 19. Bc1 Nf6 20. Bb2 Rfc8 21. Rc1 Nh7 22. Kh2 Ne8 23. d5 cxd5 24. Nxd5 Bxd5 25. cxd5 Qd7 26. Qa6 Nf8 27. Nd2 h5 28. Nf1 Bh6 29. Ne3 Nc7 30. Qb7 Ne8 31. Qxd7 Nxd7 32. Rc6 Rc7 33. Rxc7 Nxc7 34. Rc1 Ne8 35. Rc6 Rd8 36. Nd1 Nb8 37. Rc2 Na6 38. a3 Kf8 39. Bf1 Nec7 40. Nc3 Nb8 41. Nb5 Nxb5 42. Bxb5 a6 43. Bf1 Ke7 44. h4 Rd7 45. Bh3 Rb7 46. Kg2 Kd8 47. Rc8+ Ke7 48. Kf1 b5 49. Ke2 Nd7 50. Bxd7 Rxd7 51. Ra8 Rc7 52. Kd3 f5 53. exf5 gxf5 54. f4 Bg7 55. Kd2 Bf6 56. Rxa6 exf4 57. Bxf6+ Kxf6 58. gxf4 Ke7 59. Rc6 Rxc6 60. dxc6 Kd8 61. Kc3 Kc7 62. Kb3 Kxc6 63. a4 bxa4+ 64. Kxa4 1-0

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "11"]
[White "De Leon, Otto"]
[Black "Bianco, R."]
[Result "1/2-1/2"]
[ECO "B28"]
[PlyCount "48"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 c5 2. Nf3 a6 3. Nc3 Nc6 4. d4 cxd4 5. Nxd4 e5 6. Nb3 Bb4 7. Bc4 Nge7 8. 0-0 0-0 9. Nd5 Nxd5 10. Bxd5 Ne7 11. Bg5 Kh8 12. a3 f6 13. Be3 Ba5 14. Nxa5 Qxa5 15. b4 Qc7 16. f4 Nxd5 17. Qxd5 d6 18. Rad1 Bg4 19. Rd2 Rad8 20. a4 Qc8 21. Qb3 Be6 22. Qb2 Qc4 23. Bb6 Rd7 24. fxe5 dxe5 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "9"]
[White "De Leon, Otto"]
[Black "Contreras, Jose"]
[Result "1-0"]
[ECO "B92"]
[PlyCount "59"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[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. Be2 e5 7. Nb3 Be7 8. 0-0 0-0 9. Be3 b5 10. a3 Nbd7 11. f3 Bb7 12. g4 Nb6 13. Na5 Bc8 14. Nc6 Qc7 15. Nxe7+ Qxe7 16. Bxb6 Rb8 17. Bf2 b4 18. axb4 Rxb4 19. b3 Qc7 20. Bc4 Be6 21. Nd5 Bxd5 22. Bxd5 h5 23. h3 hxg4 24. hxg4 a5 25. Bc4 g6 26. Kg2 Kg7 27. Qd2 Rh8 28. Rh1 Rh7 29. Rxh7+ Nxh7 30. Rd1 1-0

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "14"]
[White "De Leon, Otto"]
[Black "Gonzales, Eliseo"]
[Result "1/2-1/2"]
[ECO "A08"]
[PlyCount "48"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. Nf3 c5 2. g3 Nf6 3. Bg2 d5 4. d3 Nc6 5. Nbd2 e5 6. e4 Be7 7. 0-0 0-0 8. h3 Rb8 9. Re1 d4 10. Nh2 b5 11. f4 Nd7 12. Ndf3 f6 13. Nh4 c4 14. f5 Bb4 15. Rf1 Ne7 16. Qg4 Qe8 17. Bf3 Ba6 18. Rd1 Bd6 19. Be2 Qf7 20. Qf3 Rfc8 21. g4 b4 22. Ng2 cxd3 23. Bxd3 Bxd3 24. cxd3 Rb6 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "16"]
[White "De Leon, Otto"]
[Black "Grimaldi, Rene A"]
[Result "1-0"]
[ECO "A06"]
[PlyCount "91"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. Nf3 Nf6 2. b3 d5 3. Bb2 c5 4. e3 Bg4 5. h3 Bh5 6. Bb5+ Nbd7 7. d3 e6 8. Nbd2 Be7 9. g4 Bg6 10. g5 Nh5 11. Ne5 0-0 12. Nxd7 a6 13. Nxf8 Kxf8 14. Bxa6 Rxa6 15. h4 Qc7 16. a4 e5 17. 0-0 e4 18. dxe4 dxe4 19. Nc4 f6 20. Qg4 Bf7 21. Qxe4 fxg5 22. hxg5 Bxg5 23. Qe5 Qc8 24. Rfd1 Qg4+ 25. Kf1 Re6 26. Qxc5+ Kg8 27. Ne5 Ng3+ 28. Kg2 Rxe5 29. Qxe5 Ne4+ 30. Kf1 Qh3+ 31. Ke1 Qh1+ 32. Ke2 Bh5+ 33. Kd3 Nxf2+ 34. Kd2 Ne4+ 35. Kd3 Nf2+ 36. Kc4 Qh4+ 37. Rd4 Bf7+ 38. Kb5 Qh5 39. Rg1 Bf6 40. Qxh5 Bxh5 41. Rd2 Bxb2 42. Rxf2 Be8+ 43. Kb6 Bc6 44. a5 Be4 45. Rf4 Bd5 46. c4 1-0

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "5"]
[White "De Leon, Otto"]
[Black "Gutierrez Herrera, Jose Antonio"]
[Result "0-1"]
[ECO "B92"]
[PlyCount "52"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[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. Be2 e5 7. Nb3 Be7 8. Bg5 Nbd7 9. Qd2 0-0 10. 0-0-0 b5 11. Be3 Bb7 12. f3 b4 13. Nd5 Nxd5 14. exd5 a5 15. Kb1 Nf6 16. Bg5 Nxd5 17. Bxe7 Qxe7 18. Bc4 Nb6 19. Be2 d5 20. Qe3 Qc7 21. Rd2 d4 22. Qg5 a4 23. Nc1 a3 24. Nd3 f6 25. Qg3 axb2 26. Nxb2 Qf7 0-1

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "13"]
[White "De Leon, Otto"]
[Black "Jimenez Molina, Juan Leon"]
[Result "1/2-1/2"]
[ECO "C98"]
[PlyCount "52"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. 0-0 Be7 6. Re1 b5 7. Bb3 0-0 8. c3 d6 9. h3 Na5 10. Bc2 c5 11. d4 Qc7 12. Nbd2 Nc6 13. d5 Na5 14. b3 g6 15. Nf1 Ne8 16. Bh6 Ng7 17. g4 f6 18. Ng3 Bd7 19. Nd2 Nb7 20. Ndf1 Nd8 21. Kg2 Nf7 22. Bd2 Rac8 23. Ne3 Nd8 24. Rf1 Nf7 25. f3 Nd8 26. Qe2 Nf7 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "1"]
[White "De Leon, Otto"]
[Black "Sabga, Fred"]
[Result "1-0"]
[ECO "C41"]
[PlyCount "55"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 d6 3. d4 exd4 4. Nxd4 Be7 5. Bd3 Nf6 6. Nc3 Nbd7 7. Nf5 0-0 8. Bg5 c6 9. 0-0 Ne5 10. Nxe7+ Qxe7 11. f4 Nxd3 12. cxd3 Qe6 13. f5 Qe7 14. Qf3 Kh8 15. Rae1 Qe5 16. Rd1 Qd4+ 17. Kh1 Nd7 18. Ne2 Qxb2 19. Rd2 Qb4 20. f6 g6 21. d4 b6 22. Bh6 Re8 23. Qf4 d5 24. e5 Nf8 25. Bg7+ Kg8 26. Qh6 Ne6 27. Rd3 Ba6 28. Qxh7+ 1-0

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "7"]
[White "De Leon, Otto"]
[Black "Torres, Luis J"]
[Result "0-1"]
[ECO "C44"]
[PlyCount "186"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 e5 2. Nf3 Nc6 3. c3 Nf6 4. d4 Nxe4 5. d5 Bc5 6. Be3 Bxe3 7. fxe3 Nb8 8. Bd3 Nf6 9. e4 d6 10. 0-0 0-0 11. Qe1 Bg4 12. Qh4 Bh5 13. Nbd2 Nbd7 14. Rae1 Bg6 15. c4 a5 16. h3 Nc5 17. Bb1 Ra6 18. g4 h6 19. Qg3 Rb6 20. b3 a4 21. Nh4 axb3 22. axb3 Bh7 23. Rf3 g5 24. Nf5 Bxf5 25. Rxf5 Nh7 26. Ref1 Kg7 27. Qc3 Na6 28. Nf3 f6 29. Qe3 c5 30. h4 Nb8 31. Kg2 Nd7 32. Rh1 Rh8 33. h5 Ra6 34. Nd2 Qa5 35. Rff1 Rha8 36. Rf2 Qb4 37. Nf1 Rb6 38. Ng3 Nhf8 39. Rhf1 Qxb3 40. Qxb3 Rxb3 41. Nf5+ Kh7 42. Nxd6 Rb6 43. Nb5 Ra4 44. Bd3 Kg7 45. Rb2 Kf7 46. Rff2 Ke7 47. Nc3 Rxb2 48. Rxb2 Ra3 49. Rc2 Nb6 50. Bf1 Nfd7 51. Ne2 Nc8 52. Ng3 Nd6 53. Kf2 Kd8 54. Bg2 Ra4 55. Nf5 Nxf5 56. exf5 Ra6 57. Rb2 Rb6 58. Ra2 Kc7 59. Be4 Kb8 60. Ke3 Rd6 61. Ra5 Rb6 62. Bc2 Ra6 63. Rb5 Ra3+ 64. Ke4 Kc7 65. Bd3 Ra7 66. Ke3 Kd6 67. Ke4 b6 68. Ke3 Ra2 69. Be4 Ra4 70. Kd3 Rb4 71. Kc3 Rxb5 72. cxb5 c4 73. Kxc4 Nc5 74. Bc2 Nb7 75. Be4 Kd7 76. Bd3 Nd6+ 77. Kc3 Nb7 78. Kc4 Kc7 79. Be2 Na5+ 80. Kb4 Kd6 81. Bf3 e4 82. Bxe4 Ke5 83. Bf3 Nb7 84. Kc4 Nd6+ 85. Kb4 Kf4 86. Bd1 Ke4 87. Bb3 Kd4 88. Ba2 Ke5 89. Bb3 Ne4 90. Bd1 Kxd5 91. Bf3 Kd4 92. Bxe4 Kxe4 93. Kc4 Ke5 0-1

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "18"]
[White "De Leon, Otto"]
[Black "Villasmil, Luis"]
[Result "1/2-1/2"]
[ECO "C45"]
[PlyCount "36"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. Nf3 Nc6 2. e4 e5 3. d4 exd4 4. Nxd4 Bc5 5. Nb3 Bb6 6. a4 a6 7. Bd3 h6 8. 0-0 Nf6 9. Nc3 d6 10. h3 0-0 11. Kh1 Ne5 12. f4 Ng6 13. a5 Ba7 14. Nd2 Bd7 15. Nf3 Bc6 16. f5 Ne5 17. Qe1 Re8 18. Qg3 Kh8 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "3"]
[White "De Leon, Otto"]
[Black "Yepez Obando, Olavo"]
[Result "1/2-1/2"]
[ECO "B43"]
[PlyCount "53"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[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 a6 5. Bd3 Qc7 6. 0-0 b5 7. a3 Bb7 8. Nc3 d6 9. Be3 Nf6 10. f4 Nbd7 11. Qe2 Be7 12. f5 e5 13. Nb3 Nc5 14. Bg5 0-0 15. Nd2 Rfe8 16. Rf3 d5 17. Bxf6 Bxf6 18. Raf1 Rad8 19. Rg3 dxe4 20. Ndxe4 Bxe4 21. Nxe4 Nxe4 22. Bxe4 Qc4 23. Re3 Bg5 24. Rd3 Rd4 25. Re1 Rxd3 26. cxd3 Qc5+ 27. Qf2 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "12"]
[White "Diaz Carias, Salvador"]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "B07"]
[PlyCount "43"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 d6 2. d4 Nf6 3. Nc3 g6 4. Bg5 Bg7 5. e5 Ng8 6. Nf3 c6 7. h3 d5 8. Qd2 f6 9. Bf4 Nd7 10. exf6 Ngxf6 11. Bh6 0-0 12. Bxg7 Kxg7 13. Ng5 Nb6 14. 0-0-0 h6 15. Nf3 Nbd7 16. Bd3 c5 17. Nh4 cxd4 18. Ne2 e5 19. Nxg6 Rf7 20. Ng3 Ne4 21. Nxe4 dxe4 22. Bxe4 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "17"]
[White "Fernan, Charles A"]
[Black "De Leon, Otto"]
[Result "1-0"]
[ECO "B08"]
[PlyCount "171"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. e4 d6 2. d4 g6 3. Nf3 Bg7 4. Bc4 Nf6 5. Nc3 0-0 6. 0-0 Nxe4 7. Nxe4 d5 8. Bd3 dxe4 9. Bxe4 c6 10. c3 Qc7 11. Re1 Nd7 12. Be3 Nf6 13. Bd3 Bg4 14. h3 Bc8 15. Qd2 Nd5 16. Bh6 Re8 17. Bxg7 Kxg7 18. Ne5 f6 19. Nf3 Qf4 20. Qxf4 Nxf4 21. Bc4 g5 22. h4 h6 23. g3 Ng6 24. h5 Nf8 25. Nh2 Bd7 26. Re3 Rad8 27. Rae1 e6 28. f4 Re7 29. f5 Be8 30. g4 Bf7 31. fxe6 Bg8 32. Nf1 Rd6 33. Ng3 Bh7 34. Nf5+ Bxf5 35. gxf5 Nh7 36. Re4 Kf8 37. Bb3 Ke8 38. c4 Rg7 39. Rg4 Ke7 40. c5 Rd8 41. Rd1 b6 42. cxb6 axb6 43. Rc1 Kd6 44. Kf2 Ra8 45. Kf3 Rc7 46. Ke4 Ra5 47. Rc3 Nf8 48. Rd3 Rca7 49. d5 c5 50. Kf3 b5 51. Rd2 c4 52. Bd1 Rxa2 53. Re2 Re7 54. Rd4 Ra5 55. Kg4 Ra8 56. Rc2 Ra2 57. Rdd2 Rc7 58. Bf3 Rca7 59. Re2 R2a4 60. Re4 Ra2 61. Rce2 Re7 62. R4e3 Ra4 63. Rc3 Rc7 64. Re4 Raa7 65. Rc1 Nh7 66. Re3 Nf8 67. Ree1 Ra4 68. Ra1 Raa7 69. Rec1 Rcb7 70. b3 Rxa1 71. Rxa1 cxb3 72. Ra6+ Ke5 73. Ra3 b4 74. Rxb3 Kd6 75. Rb2 b3 76. Bd1 Rb4+ 77. Kg3 Nxe6 78. dxe6 Rb5 79. Rxb3 Rxf5 80. Rb6+ Ke7 81. Rb7+ Kd6 82. Bb3 Re5 83. Rd7+ Kc6 84. Ba4+ Kb6 85. e7 Re6 86. Rd6+ 1-0

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "4"]
[White "Frey Beckman, Kenneth"]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "E60"]
[PlyCount "117"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. Nf3 Nf6 2. c4 g6 3. b3 Bg7 4. Bb2 d6 5. d4 0-0 6. e3 Nfd7 7. Be2 e5 8. Nc3 c6 9. Qc2 Na6 10. Ba3 c5 11. dxe5 dxe5 12. Bb2 Nc7 13. Rd1 Qe7 14. 0-0 e4 15. Nd2 f5 16. Kh1 Ne5 17. Rfe1 Be6 18. f3 exf3 19. Nxf3 Rad8 20. e4 Rxd1 21. Bxd1 Nxf3 22. Bxf3 Bc8 23. e5 Ne6 24. Nd5 Qd8 25. Nf6+ Bxf6 26. exf6 Nd4 27. Bxd4 Qxd4 28. Bd5+ Kh8 29. f7 Bd7 30. Rd1 Qe5 31. Qf2 Kg7 32. Qxc5 Rxf7 33. Qxa7 Re7 34. h3 Bc6 35. Bxc6 bxc6 36. Qd4 Qxd4 37. Rxd4 Re2 38. Rd6 Rxa2 39. Rxc6 g5 40. Rd6 f4 41. Rd3 h5 42. g3 Kf6 43. gxf4 gxf4 44. Rd5 h4 45. c5 Rb2 46. Rd3 Rc2 47. b4 Ke5 48. Rb3 Ke4 49. Rb1 f3 50. b5 Kf4 51. b6 Kg3 52. Rg1+ Kxh3 53. Rd1 Rxc5 54. Rb1 Rc2 55. Kg1 Rg2+ 56. Kf1 Rh2 57. Rb5 Kg3 58. Rg5+ Kf4 59. Rb5 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "10"]
[White "Hernandez, Gustavo2222"]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "A48"]
[PlyCount "23"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. d4 Nf6 2. Nf3 g6 3. Bg5 Bg7 4. Nbd2 d6 5. e4 c6 6. Bd3 h6 7. Bh4 0-0 8. c3 Qc7 9. 0-0 e5 10. Qc2 Nh5 11. Bg3 Nd7 12. Rad1 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "6"]
[White "Martinez, JR."]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "E67"]
[PlyCount "71"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. d4 Nf6 2. Nf3 g6 3. c4 Bg7 4. Nc3 d6 5. g3 0-0 6. Bg2 c6 7. 0-0 Nbd7 8. b3 Ne8 9. Bb2 f5 10. Ng5 Nc7 11. d5 c5 12. Ne6 Nxe6 13. dxe6 Nb6 14. Bd5 f4 15. Qc2 Be5 16. Ne4 Nxd5 17. cxd5 Bxb2 18. Qxb2 Rf5 19. Qd2 Qf8 20. Nc3 h6 21. e4 Rf6 22. f3 b6 23. Rf2 Ba6 24. Ne2 Qg7 25. Rc1 g5 26. gxf4 Bxe2 27. Rxe2 Rxf4 28. Qxf4 gxf4+ 29. Rg2 Rf8 30. Rcc2 Rf6 31. Rxg7+ Kxg7 32. Kf1 Rg6 33. Rf2 Kf6 34. Ke2 Ke5 35. Kd3 b5 36. Kc3 1/2-1/2

[Event "Caracas"]
[Site "Caracas"]
[Date "1973.??.??"]
[Round "15"]
[White "Padilla Liceaga, Jorge"]
[Black "De Leon, Otto"]
[Result "0-1"]
[ECO "E91"]
[PlyCount "68"]
[EventDate "1973.??.??"]
[EventType "swiss"]
[EventRounds "18"]
[EventCountry "VEN"]
[SourceTitle "EXT 2000"]
[Source "ChessBase"]
[SourceDate "1999.11.16"]
[SourceVersion "1"]
[SourceVersionDate "1999.11.16"]
[SourceQuality "1"]

1. d4 Nf6 2. c4 d6 3. Nc3 g6 4. e4 Bg7 5. Be2 Na6 6. Nf3 0-0 7. 0-0 c5 8. h3 Nd7 9. d5 Nc7 10. Be3 Qe8 11. Qd2 f6 12. Ne1 a6 13. a4 g5 14. f4 gxf4 15. Bxf4 Ne5 16. Nf3 Bd7 17. Nxe5 fxe5 18. Be3 Qg6 19. Kh2 Rf6 20. Rf3 Rxf3 21. Bxf3 Rf8 22. a5 Ne8 23. Ra3 Nf6 24. Rb3 Bc8 25. Ra3 Nh5 26. Bxh5 Qxh5 27. Nd1 h6 28. Nf2 Kh7 29. Ra1 Bf6 30. Rg1 Bh4 31. Nd1 Qg6 32. g3 Rf3 33. g4 Qxe4 34. Bxh6 Rd3 0-1

[Event "CACAC-chT 9th"]
[Site "Guatemala City"]
[Date "1971.??.??"]
[Round "3"]
[White "Aguilar, Pompeyo"]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "A69"]
[PlyCount "114"]
[EventDate "1971.07.31"]
[EventType "team-tourn"]
[EventRounds "9"]
[EventCountry "GUA"]
[SourceTitle "EXT 2020"]
[Source "ChessBase"]
[SourceDate "2019.10.17"]
[SourceVersion "1"]
[SourceVersionDate "2019.10.17"]
[SourceQuality "1"]
[WhiteTeam "Honduras"]
[BlackTeam "Guatemala"]
[WhiteTeamCountry "HON"]
[BlackTeamCountry "GUA"]

1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Be2 Bg7 8. f4 0-0 9. Nf3 Re8 10. Nd2 a6 11. a4 Nbd7 12. 0-0 Qc7 13. Bf3 Rb8 14. a5 b5 15. axb6 Nxb6 16. Re1 Nfd7 17. Qc2 Bxc3 18. bxc3 Nxd5 19. Nc4 N5b6 20. Nxb6 Qxb6 21. Be3 Qc7 22. Rad1 Nf6 23. Qd3 Rb6 24. c4 Qe7 25. Bd2 Be6 26. f5 Bc8 27. Ba5 Rb8 28. Qxd6 Qxd6 29. Rxd6 Nd7 30. fxg6 hxg6 31. Bc3 Ne5 32. Rf1 Nxc4 33. Rc6 Be6 34. Be2 Rbc8 35. Rxe6 fxe6 36. Bxc4 Rc6 37. Rf6 Kh7 38. Rf7+ Kh6 39. Bd2+ g5 40. h4 Kg6 41. Ra7 gxh4 42. Bc3 Rd8 43. Rg7+ Kh6 44. Rg4 Rb6 45. Rxh4+ Kg5 46. Rh3 Kf4 47. Kh2 Rc6 48. e5 Rd4 49. Bxd4 cxd4 50. Bf1 Kxe5 51. Ra3 Kf5 52. Rxa6 Rc3 53. Rd6 e5 54. Be2 Kf4 55. Rd5 Re3 56. Bc4 Rc3 57. Rd8 Ke3 1/2-1/2

[Event "CACAC-chT 9th"]
[Site "Guatemala City"]
[Date "1971.??.??"]
[Round "2"]
[White "De Leon, Otto"]
[Black "Camarena, Joaquin"]
[Result "0-1"]
[ECO "E87"]
[PlyCount "84"]
[EventDate "1971.07.31"]
[EventType "team-tourn"]
[EventRounds "9"]
[EventCountry "GUA"]
[SourceTitle "EXT 2020"]
[Source "ChessBase"]
[SourceDate "2019.10.17"]
[SourceVersion "1"]
[SourceVersionDate "2019.10.17"]
[SourceQuality "1"]
[WhiteTeam "Guatemala"]
[BlackTeam "Mexico"]
[WhiteTeamCountry "GUA"]
[BlackTeamCountry "MEX"]

1. e4 d6 2. d4 g6 3. c4 Bg7 4. Nc3 Nf6 5. f3 0-0 6. Be3 e5 7. d5 a5 8. Bd3 Na6 9. Nge2 b6 10. Qd2 Nd7 11. Bg5 f6 12. Bh6 Ndc5 13. Bxg7 Nxd3+ 14. Qxd3 Kxg7 15. h4 f5 16. exf5 Bxf5 17. Qe3 h6 18. Ng3 a4 19. Nxf5+ Rxf5 20. Ne4 Nc5 21. 0-0-0 Qe7 22. Nxc5 bxc5 23. g3 Rb8 24. Rhe1 Qf6 25. Rf1 e4 26. Qc3 Qxc3+ 27. bxc3 exf3 28. Rd3 Rbf8 29. Kb2 g5 30. hxg5 hxg5 31. Ka3 g4 32. Kxa4 Rb8 33. Rf2 Rb7 34. Ka5 Re5 35. Rdd2 Re4 36. Rb2 Rxb2 37. Rxb2 Re2 38. Rb1 f2 39. Rf1 Rb2 40. a4 Kf6 41. Ka6 Ke5 42. a5 Ke4 0-1

[Event "CACAC-chT 9th"]
[Site "Guatemala City"]
[Date "1971.??.??"]
[Round "9"]
[White "De Leon, Otto"]
[Black "Caro, Alberto Napoleon"]
[Result "1/2-1/2"]
[ECO "C44"]
[PlyCount "40"]
[EventDate "1971.07.31"]
[EventType "team-tourn"]
[EventRounds "9"]
[EventCountry "GUA"]
[SourceTitle "EXT 2020"]
[Source "ChessBase"]
[SourceDate "2019.10.17"]
[SourceVersion "1"]
[SourceVersionDate "2019.10.17"]
[SourceQuality "1"]
[WhiteTeam "Guatemala"]
[BlackTeam "Venezuela"]
[WhiteTeamCountry "GUA"]
[BlackTeamCountry "VEN"]

1. e4 e5 2. Nf3 Nc6 3. c3 Nf6 4. d4 exd4 5. e5 Nd5 6. cxd4 Bb4+ 7. Bd2 Bxd2+ 8. Nbxd2 0-0 9. Bc4 Nb6 10. Bb3 d6 11. 0-0 dxe5 12. dxe5 Qe7 13. Re1 Bf5 14. Bc2 Bxc2 15. Qxc2 Rad8 16. a3 Rd5 17. Rac1 Nxe5 18. Qxc7 Nxf3+ 19. Nxf3 Qxc7 20. Rxc7 Rd7 1/2-1/2

[Event "CACAC-chT 9th"]
[Site "Guatemala City"]
[Date "1971.??.??"]
[Round "6"]
[White "De Leon, Otto"]
[Black "Fernan, Charles A"]
[Result "1/2-1/2"]
[ECO "B48"]
[PlyCount "53"]
[EventDate "1971.07.31"]
[EventType "team-tourn"]
[EventRounds "9"]
[EventCountry "GUA"]
[SourceTitle "EXT 2020"]
[Source "ChessBase"]
[SourceDate "2019.10.17"]
[SourceVersion "1"]
[SourceVersionDate "2019.10.17"]
[SourceQuality "1"]
[WhiteTeam "Guatemala"]
[BlackTeam "Netherlands Antilles"]
[WhiteTeamCountry "GUA"]
[BlackTeamCountry "AHO"]

1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 e6 6. Be2 a6 7. 0-0 Be7 8. Be3 Qc7 9. f4 Nc6 10. Nb3 Bd7 11. Bf3 Rb8 12. Qe2 0-0 13. Rad1 b5 14. a3 Na5 15. Nxa5 Qxa5 16. Qf2 b4 17. axb4 Qxb4 18. Bd4 Bd8 19. Nb1 Bb6 20. Bxb6 Rxb6 21. b3 Rc8 22. Rfe1 Qc5 23. Qxc5 Rxc5 24. Rd2 Kf8 25. Na3 d5 26. e5 Ne8 27. Kf2 1/2-1/2

[Event "CACAC-chT 9th"]
[Site "Guatemala City"]
[Date "1971.??.??"]
[Round "5"]
[White "Hook, William"]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "A11"]
[PlyCount "97"]
[EventDate "1971.07.31"]
[EventType "team-tourn"]
[EventRounds "9"]
[EventCountry "GUA"]
[SourceTitle "EXT 2020"]
[Source "ChessBase"]
[SourceDate "2019.10.17"]
[SourceVersion "1"]
[SourceVersionDate "2019.10.17"]
[SourceQuality "1"]
[WhiteTeam "US Virgin Islands"]
[BlackTeam "Guatemala"]
[WhiteTeamCountry "ISV"]
[BlackTeamCountry "GUA"]

1. Nf3 Nf6 2. b3 g6 3. Bb2 Bg7 4. g3 d5 5. c4 c6 6. Bg2 0-0 7. 0-0 Re8 8. d3 Nbd7 9. cxd5 cxd5 10. Nc3 e5 11. Rc1 a6 12. Nd2 Nf8 13. Na4 Bd7 14. Nc5 Bc6 15. Rc2 N8d7 16. Qa1 Nxc5 17. Rxc5 Nd7 18. Rc2 f5 19. e4 dxe4 20. dxe4 Qe7 21. exf5 Bxg2 22. f6 Bxf6 23. Kxg2 Rac8 24. Rxc8 Rxc8 25. Rc1 Rxc1 26. Qxc1 Qc5 27. Qxc5 Nxc5 28. Ba3 Nd7 29. Ne4 Bd8 30. Kf3 b6 31. Ke3 Kf7 32. Kd3 Ke6 33. Bc1 Be7 34. Be3 Bd8 35. a4 Be7 36. Kc4 Bd8 37. f3 Be7 38. h3 Bd8 39. Bd2 Be7 40. Be3 Bd8 41. Bg5 Bc7 42. Bh6 Bd8 43. Ng5+ Bxg5 44. Bxg5 Kd6 45. b4 b5+ 46. axb5 Nb6+ 47. Kd3 axb5 48. Be3 Nd7 49. Bg5 1/2-1/2

[Event "CACAC-chT 9th"]
[Site "Guatemala City"]
[Date "1971.??.??"]
[Round "1"]
[White "Jorge, Gustavo"]
[Black "De Leon, Otto"]
[Result "1-0"]
[ECO "A46"]
[PlyCount "99"]
[EventDate "1971.07.31"]
[EventType "team-tourn"]
[EventRounds "9"]
[EventCountry "GUA"]
[SourceTitle "EXT 2020"]
[Source "ChessBase"]
[SourceDate "2019.10.17"]
[SourceVersion "1"]
[SourceVersionDate "2019.10.17"]
[SourceQuality "1"]
[WhiteTeam "Nicaragua"]
[BlackTeam "Guatemala"]
[WhiteTeamCountry "NCA"]
[BlackTeamCountry "GUA"]

1. d4 Nf6 2. b3 g6 3. Nd2 Bg7 4. e4 d6 5. Bb2 0-0 6. Ngf3 Nbd7 7. Be2 c5 8. 0-0 e6 9. c4 Qc7 10. Qc2 e5 11. dxe5 dxe5 12. Rfd1 Re8 13. Nf1 b6 14. Ne3 Bb7 15. Nd5 Nxd5 16. cxd5 Qd6 17. a4 a5 18. Bb5 Ba6 19. Qd3 Bxb5 20. Qxb5 Bh6 21. Qc6 Qe7 22. Bc1 Bxc1 23. Raxc1 Rac8 24. Qb5 Qd6 25. Nd2 Rb8 26. Nc4 Qc7 27. Rc3 Nf6 28. f3 Qd7 29. Qa6 Qc8 30. Qxc8 Rexc8 31. Nxe5 Rb7 32. Nc4 Rd8 33. Rcd3 Kg7 34. e5 Ne8 35. f4 Kf8 36. g4 h6 37. Kf2 Kg7 38. h4 f6 39. Kg3 Kh7 40. Re1 Rg7 41. e6 Rd6 42. f5 Re7 43. Ree3 Rb7 44. Nxd6 Nxd6 45. e7 Ne8 46. fxg6+ Kxg6 47. Re6 Rc7 48. Rde3 Rd7 49. Rxb6 Rxd5 50. Rb5 1-0

[Event "CACAC-chT 9th"]
[Site "Guatemala City"]
[Date "1971.??.??"]
[Round "7"]
[White "Mena, Leonardo"]
[Black "De Leon, Otto"]
[Result "1-0"]
[ECO "B09"]
[PlyCount "111"]
[EventDate "1971.07.31"]
[EventType "team-tourn"]
[EventRounds "9"]
[EventCountry "GUA"]
[SourceTitle "EXT 2020"]
[Source "ChessBase"]
[SourceDate "2019.10.17"]
[SourceVersion "1"]
[SourceVersionDate "2019.10.17"]
[SourceQuality "1"]
[WhiteTeam "El Salvador"]
[BlackTeam "Guatemala"]
[WhiteTeamCountry "ESA"]
[BlackTeamCountry "GUA"]

1. e4 d6 2. d4 Nf6 3. Nc3 g6 4. f4 Bg7 5. Nf3 0-0 6. Bd3 c5 7. dxc5 dxc5 8. e5 Nd5 9. Nxd5 Qxd5 10. Qe2 Nc6 11. Be4 Qd8 12. Be3 Qc7 13. 0-0-0 b6 14. Kb1 Bb7 15. h4 e6 16. h5 Rfd8 17. Rxd8+ Nxd8 18. Bd3 Rc8 19. hxg6 fxg6 20. c3 Bxf3 21. Qxf3 Qf7 22. Qh3 Bf8 23. g4 c4 24. Be4 Rc7 25. f5 Qg7 26. fxg6 hxg6 27. Bg5 Be7 28. Be3 Nf7 29. Ka1 Bg5 30. Bd4 Be7 31. Qh2 Bg5 32. Qc2 Nh8 33. Qg2 Nf7 34. Bc2 Kf8 35. Qe4 Kg8 36. Qxg6 Qxg6 37. Bxg6 Kg7 38. Bc2 Rd7 39. b3 b5 40. Bf5 Re7 41. Rh7+ Kg8 42. Bg6 cxb3 43. axb3 a6 44. Kb2 Rd7 45. Rxf7 Rxf7 46. Bxf7+ Kxf7 47. c4 bxc4 48. bxc4 Bd8 49. Be3 Bc7 50. Bf4 Kg6 51. c5 Kf7 52. Kc3 Kg6 53. Kc4 Kg7 54. Kd4 Kg6 55. Bc1 Bd8 56. Ba3 1-0

[Event "CACAC-chT 9th"]
[Site "Guatemala City"]
[Date "1971.??.??"]
[Round "8"]
[White "Pena, Gustavo"]
[Black "De Leon, Otto"]
[Result "1/2-1/2"]
[ECO "A77"]
[PlyCount "81"]
[EventDate "1971.07.31"]
[EventType "team-tourn"]
[EventRounds "9"]
[EventCountry "GUA"]
[SourceTitle "EXT 2020"]
[Source "ChessBase"]
[SourceDate "2019.10.17"]
[SourceVersion "1"]
[SourceVersionDate "2019.10.17"]
[SourceQuality "1"]
[WhiteTeam "Dominican Republic"]
[BlackTeam "Guatemala"]
[WhiteTeamCountry "DOM"]
[BlackTeamCountry "GUA"]

1. d4 Nf6 2. c4 c5 3. d5 e6 4. Nc3 exd5 5. cxd5 d6 6. e4 g6 7. Be2 Bg7 8. Nf3 a6 9. a4 0-0 10. 0-0 Re8 11. Nd2 Nbd7 12. f3 b6 13. Nc4 Ne5 14. Bg5 Nxc4 15. Bxc4 h6 16. Be3 Kh7 17. Qd2 Ra7 18. Rab1 Ra8 19. b4 Nd7 20. Rfc1 Ne5 21. Bf1 Nd7 22. Kh1 Qe7 23. Nd1 Bf8 24. Bf4 Qf6 25. Nf2 Qd8 26. Ng4 h5 27. Nf2 f6 28. h4 Qe7 29. Nd3 Qd8 30. Be2 Qe7 31. Rg1 c4 32. Ne1 b5 33. a5 Ne5 34. Nc2 Bd7 35. Nd4 Rac8 36. Rbc1 Bg7 37. Bd1 Qf7 38. Be2 Bh6 39. Nc2 Bg7 40. Nd4 Qe7 41. Rgd1 1/2-1/2

