[Event "Olympiad-19 Preliminaries A"]
[Site "Siegen"]
[Date "1970.09.10"]
[Round "6"]
[White "Yabra, Frederico"]
[Black "Kchouk, Bechir"]
[Result "0-1"]

1. d4 Nf6 2. Nf3 g6 3. c4 Bg7 4. g3 O-O 5. Bg2 d6 6. O-O c6 7. Nc3 Nbd7 8. Qc2 Nb6 9. b3 d5 10. c5 Nbd7 11. Bb2 e5 12. dxe5 Ng4 13. Rad1 Qe7 14. e4 dxe4 15. Nxe4 Ndxe5 16. Nd6 Be6 17. Rfe1 Nxf3+ 18. Bxf3 Nf6 19. b4 a6 20. Bg2 Qc7 21. Be5 Nd5 22. Ne8 Qxe5 23. Rxe5 Bxe5 24. Bxd5 Bxd5 25. Nd6 Bxd6 26. cxd6 Rad8 27. a3 Rxd6 28. f4 Re8 29. f5 Be4 30. Qe2 Rxd1+ 31. Qxd1 Bxf5 32. g4 Be6 33. g5 Bd5 34. Qg4 Re6 35. Qf4 b5 36. Qb8+ Kg7 37. Kf2 h6 38. h4 hxg5 39. hxg5 Re4 40. Qd8 Re6 41. Qb8 Re4 42. Qc7 Rh4 43. Kg3 Re4 44. Kf2 Rc4 45. Qe5+ Kf8 46. Qc7 Rc2+ 47. Kg1 Ra2 48. Qc8+ Ke7 49. Qxa6 Rg2+ 50. Kf1 Rxg5 51. Kf2 Re5 52. Qa7+ Kf6 53. Qb8 Kf5 54. Qh8 Re4 55. Qh3+ Ke5 56. Qc3+ Ke6 57. Qg7 Rg4 58. Qh8 f5 59. Qe8+ Kf6 60. Qh8+ Kg5 61. Qd8+ Kf4 62. Qd6+ Ke4 63. Qc5 Kd3 64. Qc1 Rg2+ 65. Kf1 Be4 66. a4 bxa4 67. Qd1+ Kc3 68. Qxa4 Rb2 69. Qa1 Kb3 70. Qa5 g5 71. Ke1 g4 72. Qe5 Rc2 73. Qd6 Rc3 74. Qb8 g3 75. b5 c5 76. Qg8+ c4 77. Qg5 g2 78. Kf2 Rc2+ 0-1