[Event "Budapest"] [Site "?"] [Round "0"] [White "Petrosian"] [Black "Keres"] [Result "1-0"] [ECO "E46"] [Opening "Nimzo-Indian: 4.e3 O-O"] 1. d4 Nf6 2. c4 e6 3. Nc3 Bb4 4. e3 O-O 5. Nf3 d5 6. Bd3 c5 7. O-O b6 8. dxc5 bxc5 9. Ne2 {9.cxd5 exd5 would leave Black with hanging pawns.} 9... Nbd7 10. b3 {White wishes to keep an eye on the Black center with 10. b3 and Bb2. Although strategically correct 10. b3 has a tactical flaw. 10.Ng3 would be better, since, it would allow White to control the center after 10... e5 11. cxd5 e4 12. Nxe4.} 10... e5 11. Bb1 e4 {11...d4 looks strong. However, White would get good play after 12.Ng3 Bb7 13.a3 Ba5 14.b4} 12. Nd2 Ba6 13. Bb2 { 13.cxd5 would drop material after 13...Bxe2 14. Qxe2 Bc3 winning the rook.} 13... Qa5 {Qa5 looks good at first since Black has a double attack on the White knight. However, it does nothing to increase Black's main advantage of time and space. Furthermore, White has a strong tactic to save the piece. 13... Nb6 would put more pressure on White's position for example 14.cxd5 Qxd5 15. Bxf6 Qxd2 winning material because of the pin at e2.} 14. Nxe4 {With this tempo rary sacrifice, White is able to trade his knight for the Black bishop.} 14... dxe4 15. a3 Bd2 16. b4 cxb4 { 16...Qb6 17.Qxd2 Bxc4 would leave chances for both sides.} 17. Qxd2 Bxc4 18. axb4 Qg5 {Better was 18...Qb6 not losing a tempo with the queen.} 19. Ra5 { With this move White gains a tempo on the Black queen.} 19... Qh4 {19...Qg4 wo uld be better. The idea is to centralize the Black queen after 20.Re1 Qe6} 20. h3 Rfb8 21. Ng3 Rb5 {21...Bxf1 would drop the Black queen after 22.Nf5 Qh5 23. Ne7+ Kf8 24.Rxh5 when White is winning on account of his material advantage.} 22. Rxb5 Bxb5 23. Rc1 Bd3 24. Bxd3 exd3 25. Bd4 Ne4 26. Qxd3 Nxg3 27. fxg3 Qxg3 28. Qe4 {White takes advantage of Black's weakened back rank.} 28... Rd8 29. Qe7 Qb8 {Forced. Here White uses a deflection theme combined with the back rank weakness to achieve victory. Do you see White's next move? Try to find it!} 30. Bxa7 Qxa7 {Taking the bishop loses the exchange, but Black would still be lost, because of his inactive pieces and material deficit. 30...Qa8 31.Rc7 would leave Black in Zugzwang.} 31. Qxd8+ Nf8 32. Qe8 {White must not bring the rook down to the 8th rank too quickly! 32. Rc8 Qxe3+ 33.Kh2 Qe5+ 34. Kg1 Qe1+} 32... Qa3 33. Rc7 { Threatening to mate in two with 34. Qxf7+ and 35. Qxg7++.} 33... Qb3 34. Qe7 Qd5 35. Kh2 h6 36. Rc8 { Black resigned as he has no way of defending the knight on the back rank.} 1-0