[Event "Holland"]
[Site "?"]
[Date "1939.??.??"]
[Round "6"]
[White "Keres"]
[Black "Euwe"]
[Result "1-0"]
[PlyCount "109"]

1. d4 { Paul Keres, the greatest player to come from Estonia, was probably the best player never to become World Champion. Here he defeats the reigning title- holder of the time. } 1... Nf6 2. c4 e6 3. Nc3 Bb4 4. Qc2 Nc6 5. Nf3 O-O 6. Bg5 h6 7. Bh4 d6 { The pin may be annoying, but it cannot easily be broken, as Botvinnik pointed out: 7...g5? 8.Bg3 g4 9.Nh4 Nxd4 10.Qd2! Nf5 11. Nxf5 exf5 12.Qxh6 } 8. e3 Qe7 9. Be2 e5 { Black has treated the center with classical respect, and White must decide whether he should capture, advance, or maintain the status quo. } 10. d5 Nb8 { The correct move. Now that White has conceded control of c5, that square will be the natural home for the knight. From b8 it only takes two moves to reach c5. } 11. Nd2 { This move serves many purposes. It breaks the pin on the Nc3, and overprotects e4. Now if an eventual g7-g4, Black cannot gain more time with g5-g4. White will also be able to attack with a pawnstorm on the kingside. } 11... Nbd7 12. O-O a5 13. Rae1 { The Rf1 should remain in place because it supports the advance of the f- pawn. There is no need to worry about action on the queenside, because White's pieces enjoy such freedom of movement that they can switch sides quickly. } 13... Re8 { This is aimed at preventing White from going after the weak square c7 with Nc3-b5. 13...Nc5 would have been consistent with Black's plans and might have been better than the text. } 14. f4 { 14.Nb5 Bxd2 15.Qxd2 Ne4 16.Qc2 Qxh4 17.Nxc7 Qd8 18.Nxa8 Ndc5 and the knight is trapped. } 14... Bxc3 15. Qxc3 Ne4 16. Nxe4 Qxh4 17. g3 Qe7 { Now White must think of a plan. Clearly his bishop is not a long- term asset, and if Black plays f5-f5, it will be difficult to exchange. } 18. Bg4 { This assures that the bishops will come off the board, and then the pawn structure will favor White. The threat of 19.Bxd7 Bxd7 20.f5! is quite strong and therefore Black must exchange both sets of minor pieces. } 18... Nf6 { 18...Nf8? 19.Bxc8 Raxc8 20.f5 secures a significant spatial advantage. } 19. Nxf6+ Qxf6 20. Bxc8 Raxc8 { After avoiding 21.Qxa5? exf4!, White must reconfigure his position so that his rooks will be effective on an open line. Which file? } 21. Rf2 { This exploits the pin on e5, since the double-rook endgames favor White. Now Keres will gain more space on the kingside by playing f4-f5, after which he can concentrate on the queenside. } 21... b6 22. Ref1 Qg6 23. f5 Qf6 24. e4 { Given the fact that White's pieces enjoy superior mobility, it is possible for him to preserve chances on both sides of the board by locking the center. The threat of a kingside pawn storm will trouble Black for some time. } 24... c6 { This approach to the problem is too radical, or at least premature, since White has not yet weakened his queenside by advancing the pawns there. } 25. dxc6 Rxc6 { Now White has opened some lines and useful light squares, and Black now has to defend the weaknesses at b6 and d6. But Black threatens 26...b5! } 26. a4 Kf8 27. Rd1 Rec8 28. b3 Ke7 { Black has now secured his queenside, but the kingside is defended only by the queen. Before undertaking action there, White will have to bring his own queen into play and ensure that his rooks can move freely on the f- and g-files. } 29. Qf3 Kd7 30. h4 Kc7 31. Kf1 { The king crawls out of the way, so that the rooks can do their job. } 31... Kb7 32. Ke2 R8c7 33. Rh2 Qd8 34. g4 f6 35. Rg2 Rc8 { It is easy to see that the only way White can win is by a properly timed g4-g5 but at the same time he must make sure that Black is tied to the defense of d6 } 36. Rg3 Qd7 37. Qd3 Qf7 38. Rh1 Rh8 39. Rhh3 Rcc8 { Black now offers the d6-pawn as a sacrifice, since he will receive more than enough compensation if control of the d-file is granted to him. But White correctly keeps the position closed in the center, and breaks on the kingside. } 40. g5 hxg5 41. hxg5 Qc7 { 41...Rxh3 42.Rxh3 fxg5 would allow White to capture at d6, since the d-file could not be contested. } 42. Qd5+ Ka7 43. Rd3 Rxh3 { The sealed move. The alternative was to go into a rook endgame. 43...fxg5 44.Rxh8 Rxh8 45.Qxd6 Qxd6 46.Rxd6 Rh4 47.Kf3 Rh3+ 48.Kg4 Rxb3 49.Rd7+ Ka6 50.Rxg7 and the f-pawn decides. } 44. Rxh3 fxg5 45. Rh7 { The threat of f5-f6 forces Black to adopt a passive defense, and that allows the White king to take an active part in the game. } 45... Qe7 46. Kf3 Rf8 47. Kg4 Rf7 { White has achieved a lot, but he must now find a way to exploit his spatial advantage. He needs open lines against the Black king! } 48. b4 axb4 { 48...Qc7 49.bxa5 bxa5 50.Rh8 or 48...Qb7 49.Qxb7+ Kxb7 50.b5 is hopeless for Black. } 49. a5 { White relentlessly forces open lines, knowing that the rook on h7 only appears to be out of play. In fact, it can get to the queenside in two moves, via h8 or h1. } 49... Qb7 50. axb6+ Kxb6 51. Qxd6+ Ka7 52. Qxe5 b3 53. Rh3 { A fine move, which prevents the advance of the b-pawn because of Ra3+. Now Black cannot afford to exchange queens, as when the b-pawn falls the endgame is a trivial win for White. } 53... Rf6 54. Qd4+ Rb6 55. Rxb3 1-0