[Event "Interzonal-10a"]
[Site "Biel"]
[Date "1976.07.22"]
[Round "9"]
[White "Castro Rojas, Oscar Humberto"]
[Black "Petrosian, Tigran V"]
[Result "1-0"]
[WhiteElo "2380"]
[BlackElo "2635"]

1. e4 e6 2. b3 d5 3. Bb2 Nf6 4. exd5 exd5 5. Nf3 Be7 6. Be2 O-O 7. O-O Bf5 8. Re1 c5 9. d4 Nc6 10. Nbd2 Rc8 11. Bd3 Bxd3 12. cxd3 Qb6 13. Ba3 Rfe8 14. Rc1 Nb4 15. Bxb4 Qxb4 16. Nf1 cxd4 17. Rxc8 Rxc8 18. Nxd4 Bf8 19. Nf3 Qa3 20. Qb1 g6 21. Ne3 Bg7 22. h3 a6 23. g3 b5 24. Nc2 Qd6 25. Ne3 d4 26. Ng4 Nd5 27. Ng5 h6 28. Nf3 Qa3 29. Qd1 Qxa2 30. Nfe5 Nc3 31. Qf3 Qxb3 32. Nd7 Rd8 33. Ndf6+ Kh8 34. Ne5 a5 35. Qb7 Rf8 36. Ned7 Rd8 37. Ne5 Rf8 38. Ned7 Rd8 39. Qc7 Ra8 40. Qb7 Rd8 41. Re7 Bxf6 42. Nxf6 Kg7 43. Qc7 Ra8 44. Qe5 Kf8 45. Qd6 Qb4 46. Re8+ Kg7 47. Rxa8 Qxd6 48. Ne8+ Kh7 49. Nxd6 a4 50. Ne4 b4 51. Nc5 a3 52. Nb3 1-0