[Event "Candidates' Tournament"] [Site "?"] [Round "0"] [White "Petrosian"] [Black "Olafsson"] [Result "1-0"] [ECO "E21"] [Opening "Nimzo-Indian: Three Knights"] 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. Nf3 c5 5. e3 O-O 6. Be2 b6 7. O-O Bb7 { This is a typical hypermodern handling of the opening by Black, who has indirect pressure on the center.} 8. Na4 cxd4 9. exd4 Be7 10. a3 {A useful move which prepares to gain space on the queenside with pawn b4 and then fianchetto the queen bishop.} 10... Ne4 {An excellent central post for the knight.} 11. b4 f5 12. Bb2 Bf6 {Perhaps better was an immediate 12...d6 with the idea of reinforcing the knight with Nbd7, Ndf6.} 13. Qb3 d6 14. Nc3 { White brings his out of play knight back into the game.} 14... Qe7 15. Rad1 Nd7 16. Nxe4 fxe4 {Black is fully justified in doubling his e-pawns because of the play down the newly opened f-file.} 17. Ne1 Bg5 18. Nc2 Rf7 { Black prepares to double his rooks on the f-file.} 19. Bc1 Bxc1 20. Rxc1 Raf8 { An interesting position has arisen with White having an advantage on the queenside, while Black's pieces have been building up on the kingside.} 21. Ne3 Ba8 {21...Qg5 would have been more to the point.} 22. Rc2 Kh8 23. a4 { While Black's last two moves have done little to further his kingsideadvantage. White has followed a consistent plan on the queenside.} 23... Qg5 24. Qa3 Rf6 25. Ra2 h5 26. a5 Bb7 27. Qc3 R8f7 28. axb6 axb6 {Take notice of Black's wrecked pawn structure. The weak pawns will be especially hard to defend in the endgame.} 29. g3 Nf8 30. h4 Qh6 31. Ng2 g5 32. hxg5 Qxg5 33. Qe3 Qg7 34. Bxh5 Rc7 35. Be2 Rh6 36. f4 exf3 37. Bxf3 Qxg3 { Black resigned. 37...Qxg3 Black resigned in view of...} 38. Qxh6+ Nh7 39. Bxb7 Rxb7 40. Rf8+ 1-0