World Championship
The 21st game sealed Petrosian's fate. The loss left him two points down with only three to go in the scheduled best of 24 games match. Spassky, by drawing both the 22nd and 23rd games reached the required 12½ pts. to take the title.
Boris Spassky vs Tigran V Petrosian
Petrosian - Spassky World Championship Match (1969), Moscow URS, rd 21, Jun-11
Spanish Game: Closed Variations. Keres Defense (C92) 1-0
1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O Be7 6. Re1 b5 7. Bb3 O-O 8. c3 d6 9. h3 Nd7 10. d4 Bf6 11. Be3 Na5 12. Bc2 Nc4 13. Bc1 Bb7 14. b3 Ncb6 15. Be3 Re8 16. d5 Rc8 17. Nbd2 c6 18. c4 cxd5 19. cxd5 Qc7 20. Rc1 Qb8 21. a4 Nc5 22. axb5 axb5 23. Ra1 b4 24. Qe2 Nbd7 25. Bd3(a) Nxd3(b) 26. Qxd3 Ba8 27. Nc4 Nc5 28. Bxc5(c) Rxc5 29. Ra4 h6 30. Qd2 Be7 31. Rea1 Bb7 32. Qxb4 f5(d) 33. Ra7 Rc7 34. exf5 Qc8 35. Ne3 e4 36. Nd4 Bf6 37. Rf1 Ba6 38. Rxc7 Qxc7 39. Qa4 Ra8 40. Rd1 Qb8 41. Nc6 Qb7 42. Qxe4 Qxb3 43. Re1 Bc3 44. Rb1 Qa2 45. Nb4 Qa4 46. Qe6+ Kh8 47. Qxd6 Be2 48. Nc6 Qa2 49. Rb8+ Rxb8 50. Qxb8+ Kh7 51. Qg3(e) Bh5 52. Kh2 Be1 53. f6 Resigns(f)
(a) To meet 25. … B-R3; 26. Q-Q1 B-Q6.
(b) As the NY Times points out, Black missed his big chance here with 25. … BxQP!, activating his Bishop, for if now 26. PxB P-K5 with advantage.
(c) White readily exchanges the Bishops as his two knights are much more effective in this position.
(d) At last attempting to break the centre, but it is too late.
(e) Not 51. N-K7 Q-R8ch; 52. K-R2 B-K4ch.
(f) Mate in a few moves is inevitable. 53. … PxP; 54. N-B5 B-N3; 55. Q-B7ch. Or, 53. … P-N4; 54. Q-B7ch K-N3; 55. Q-N7 mate.