1.d4 Anand decides to open the game with the d-pawn, as he did in his World Championship match against Kramnik in Bonn 2008.
1...Nf6 2.c4 e6 3.Nf3 No Nimzo today. Against Kramnik Anand used Nimzo and it brought him a point and a good position in game 2.
3...d5 Topalov doesn't go for the safe Queen's Indian, but rather for a sharp Ragozin or Vienna.
4.g3 No! Anand goes for a calm Catalan, which was and still is a great weapon of another world champion – Kramnik.
4...dxc4 5.Bg2 a6!? Diagram The idea of this line is to save the pawn by any means.
6.Ne5 [6.0-0 is another main line, which is a real pawn sacrifice.]
6...c5 7.Na3 [7.Be3 Nd5 8.dxc5 Was played recently by other Catalan players, Bacrot and Wang Yue.]
7...cxd4 8.Naxc4 Bc5 Diagram [8...Ra7 is another possibility, with the idea b6. I remember it from the game Wang Yue-Van Wely from Corus 2009, where black equalised without problems. But I guess Anand had an improvement there.]
9.0-0 0-0 10.Bd2 Nd5 11.Rc1 Nd7 12.Nd3 Ba7 Diagram So far both players played logical moves, but from here White has a big and wide choice.
13.Ba5 A questionable decision. [13.Qb3!? Made sense, since later on Black was threatening b6, attacking the bishop on a5. But perhaps Anand has analyzed this position deeply and came to conclusion that it is better to include Ba5 Qe7. If 13...Nc5 then simple 14.Nxc5 Bxc5 15.Ne5 and White keeps up the pressure. (15.Ba5!? ) ]
13...Qe7 14.Qb3 Rb8 Preparing b6. Now white had a big choice and I am afraid Anand chose not the best move, though later it worked out well for him. [After 14...b6 White has 15.Bb4 Nc5 16.Qa3 Bb7 17.Bxd5! Bxd5 18.Nxb6! Bxb6 19.Bxc5 Bxc5 20.Rxc5 With some pressure and edge.]
15.Qa3?! Diagram As I said, later it worked out well for Anand. At the time I doubted the objective evaluation of the move, but after seeing the whole game I was wondering – maybe it was pure genius, from a psychological point of view!? [15.Rfd1! Is the move I like most. Now Black doesn't have a very useful move, since 15...b6 falls into (15...Nc5 16.Nxc5 Bxc5 17.Ne5 should also be slightly better.; 15...Re8!? or; 15...h6 are maybe the best moves, but White can then try Qa3 or improve slowly with let's say Rc2.) 16.Bb4! Nc5 17.Qa3 Bb7 (17...Nxb4 18.Nxb4 Bb7 19.Bxb7 Qxb7 20.Rxd4 ) 18.Bxd5! Bxd5 19.Nxb6! Bxb6 20.Rxc5! Bxc5 21.Bxc5 Qb7 22.Bxf8 Rxf8 23.Qb4 With advantage for White.]
15...Qxa3 16.bxa3 Diagram
16...N7f6?! logical, [but the more logical 16...Nc5! was the move. I think White would have to fight for the draw, and I am curious what Anand wanted to play here and what Topalov was afraid of.]
17.Nce5! Now I liked the white position again, though I think he has no objective advantage.
17...Re8! preparing b6 and Bd7 [17...b6 18.Bb4! ; 17...Bd7 18.Nxd7 Nxd7 19.Bxd5 exd5 20.Rc7+/= ]
18.Rc2 [18.g4!? looks interesting too.]
18...b6?! objectively must be okay, but I think if there is no need to weaken the c6 square, then why to do it?! [I prefer 18...Bd7! not weakening c6. Now the best white can do is 19.Nxd7 Nxd7 20.Rfc1 N7f6 21.Ne5 which should be around equal. White has two bishops and good pieces, while black has an extra pawn and a solid position with no weaknesses.]
19.Bd2 Bb7 20.Rfc1 Stronger than the immedeate Nc6. In general Anand plays very well from now on, without forcing things too much, just improving the position, no caring that he is a pawn down.
20...Rbd8 21.f4 Bb8 22.a4 a5 23.Nc6 Diagram Now that White has made all the useful moves, it is time for this exchange.
23...Bxc6 24.Rxc6 h5?! A strange, impulsive and weakening move, although again, objectively it is not a mistake. [24...h6 would be played by a more patient defender.]
25.R1c4 Diagram [25.Bf3!? Immediately pointing at the h5 pawn.]
25...Ne3? Now the real mistake comes. I think Topalov got tired of making moves without any idea. He wanted to force things. However there was another way... [25...Ng4! Fits perfectly with h5. If Topalov could have played it, I would have to give h5 an exclamation mark! 26.Bf3 (26.Rxd4 Ba7! is the point. Now White would be in trouble.) 26...e5! (26...Ba7!? is not human, but not a bad move either.) 27.fxe5 Nxe5 28.Nxe5 Bxe5 29.Kf1 should be aroung equal, with Black having no problems after (29.Bxh5 d3! 30.exd3 Ne7-/+ ) 29...h4! ]
26.Bxe3 dxe3 27.Bf3!? Diagram [27.Rxb6 Was of course another option, but Anand is trying to confuse Topalov, offering him a difficult choice between giving up the h5 and b6 pawn. And he also perhaps didn't like 27...e5!? ]
27...g6? [27...Nd7 was I think better, but White had a pleasant advantage there as well. Still it was way better than what Topalov go in the game. 28.Bxh5 e5! being the idea]
28.Rxb6 Now there is no e5, and the a5 pawn is extremely weak.
28...Ba7 [28...Re7 Trying to defend a5 with Bc7 was better. Surprisingly White is unable to win the pawn by force, but obviously he still has a big advantage.]
29.Rb3! So that Topalov can forget about any Rxd3.
29...Rd4 30.Rc7 Bb8 31.Rc5! Diagram a4 is untouchable due to Bc6 and White wins the a5 pawn.
31...Bd6 32.Rxa5 Rc8 Black is getting active, but it won't give him anything. White has a good protection of the key d3 and e2 squares and the a-pawn (supported by a long-sighted bishop who keeps on looking at a8, the promotion square) should decide the game in White's favour.
33.Kg2 I love these moves. I can imagine how disgusted Topalov must be with his position now.
33...Rc2 34.a3 The mean World Champion, who already gave the pawn once in the opening, doesn't want to give it now anymore. And he is right... this will be the decisive pawn!
34...Ra2?! [34...Nd5 It was necessary to still try to complicate the matter a bit, but White is winning anyway.]
35.Nb4! Diagram All suporters of Anand were now very relieved when they saw the black king standing on g8, not g7...
35...Bxb4 [35...Rxa3 36.Rxa3 Bxb4 37.Ra8+! is what I meant with my previous comment.]
36.axb4 Nd5 37.b5! The a4 pawn doesn't matter anymore, while it's colleague runs!
37...Raxa4 38.Rxa4 Rxa4 39.Bxd5! Killing the knight. The arising ending is the most winning rook ending I ever saw in my life.
39...exd5 40.b6 Ra8 41.b7 Diagram At the end the decisive factor is – the a-pawn! The little a-pawn that was standing on a2 at the beginning of the game.
41...Rb8 42.Kf3 d4 43.Ke4 Diagram A great comeback by the World Champion, though I must add that it was obviously not without help from Topalov. 1-0