1.d4 d5 2.c4 c6 Apparently, during the last three games Kramnik has managed to convince his opponent that the Slav is not such a bad opening after all.
3.Nf3 Nf6 4.Nc3 e6 But only this must have been the real surprise for Kramnik! Topalov usually employs the ...a6 systems and only accidentaly played the Semislav throughout his carrier. If his intention was to confront Kramnik with the unpleasant psychological situation of fighting against his own weapons, we can safely state that the experiment has been crowned with success.
5.e3 Nbd7 [Even here, Topalov preferred 5...a6 in his game against Ponomariov, played at Sofia 2006.]
6.Bd3 dxc4 7.Bxc4 b5 8.Be2 Kramnik is consistent with his policy of avoiding sharp opening lines. The modest bishop retreat to e2 is supposed to offer White little chances for an advantage, but even less danger of getting into trouble.
8...Bb7 9.0-0 b4 Topalov's desire to take his oppponent out of the well-known paths as soon as possible becomes obvious. Black usually plays 9...Be7 here or, even more frequently, 8...a6.
10.Na4 c5 11.dxc5 Nxc5 12.Bb5+ Ncd7 13.Ne5 Qc7 14.Qd4 Rd8 15.Bd2 Looking at this position, I have the feeling as if players would have changed places with each other. It is Kramnik who has a slight advance in development, while Topalov mainly relies on the solid character of his position. Quite opposite with what we have seen during the last few days.
15...Qa5N And now, Topalov moves for the second time with his already developed queen, something that Kramnik did frequently in the first part of the match. The move is a novelty, which is quite curious because it is the computer's first suggestion. We can suppose that Kramnik had looked at it at home (even though not especially for this game or match) and the time spent on the next moves was destined to let him remember the old analysis.
16.Bc6 Be7 17.Rfc1 [This looks like the more logical way of maintaining the advance in development, but knowing the further course of the game it is easy to recommend 17.b3 instead.]
17...Bxc6 18.Nxc6 Qxa4 19.Nxd8 Bxd8 20.Qxb4 Qxb4 21.Bxb4 Nd5 22.Bd6 At first glance it might look as if White is doing just great. His material deficit is almost insignificant, while his rooks are ready to invade the enemy queen side. However, there is a certain detail that favours Black: the centralized position of his king. Since the white king would need considerable amount of time to get into play, we can state that for practical purposes Black is a whole... king up! From this point of view, Kramnik's 20th move is slightly questionable. In order to prove 17.Rfc1 to be playable, White needs to exchange queens only after Black gets castled. The only open question remains whether this can be achieved in practice.
22...f5 23.Rc8 N5b6 24.Rc6 Be7 25.Rd1 Kf7 26.Rc7 Ra8 27.Rb7 Ke8 Black's last three moves can be considered some sort of artificial (but huge) castle.
28.Bxe7 Kxe7 29.Rc1 a5 30.Rc6 Nd5 Both sides have completed the first phase of piece mobilisation. The placement of the white rooks creates a strong optical impression, but they fail to create any serious threats. With the e6-pawn and the d7-knight safely defended by the king, Black has little to fear here. At the same time, the transfer of the white king to the queen side is highly problematic, because of the numerous possible forks.
31.h4?! "Do not move pawns on the wing where you are weaker" they say. It is remarkable how much quicker Black will make progress on this wing after White's unnecesary pawn move.
31...h6 32.a4 g5 33.hxg5 hxg5 34.Kf1 g4 Now, White has to permanently reckon with the enemy rook's penetration through the h-file or the pawn break ...g3.
35.Ke2 N5f6 The start of a highly original manoeuvre.
36.b3 Ne8! [Black intends to drive the enemy rook away from the b-file by means of ...Nd6. The seemingly more active 36...Ne4 , bearing the same idea, would have been less accurate in view of 37.Rcc7 ]
37.f3 It is hard to apply to this move the same kind of criticism as to White's 31st move. Kramnik must have felt that he is rapidly losing ground and aimed to exchange as many pawns as possible.
38.Rc1 Nef6 Now that White has weakened his king side, the knight changes plans.
39.f4 But this looks like suicide already. White weakens his structure even more, in order to get the possibility to attack the g3-pawn, without noticing that it is posioned.
39...Kd6 40.Kf3 Nd5 41.Kxg3? White offers to his opponent the only thing that he was missing yet: an open file for attack.
41...Nc5 42.Rg7 Rb8 43.Ra7 Rg8+ 44.Kf3 Ne4 Black has a decisive attack already.
45.Ra6+ Ke7 46.Rxa5 Rg3+ 47.Ke2 Rxe3+ 48.Kf1 Rxb3 49.Ra7+ Kf6 50.Ra8 Nxf4 51.Ra1 Rb2 52.a5 [Allowing mate in 5. However, 52.Rg8 would have failed to safely defend the g2-square because of 52...Kf7 ]