The third successful pawn sacrifice in the match. On the evidence of the match so far, both of these players seem more comfortable having the initiative.
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A blow for Topalov's self-confidence but he now has a rest day to digest this loss and get himself ready for the fifth game when he will have White.
The game with my annotations follows on below:
Viswanathan Anand (2787) - Veselin Topalov (2805)
Sofia WCM (4th game) 28.04.2010
Catalan opening (E04)
1.d4 ♘f6 2.c4 e6 3.♘f3 d5
In other circumstances (when he needs to win at all costs) Topalov might essay the more double-edged 3...c5.
4.g3 dxc4 5.♗g2 ♗b4+
The Bulgarian varies from the second game, although his position wasn't that bad after the opening (despite the eventual result!).
6.♗d2 a5 7.♕c2 ♗xd2+ 8.♕xd2 c6 9.a4 b5
A new move and quite a good-looking one.
Instead the sequence 10.axb5 cxb5 11.♕g5 0-0 12.♕xb5 ♗a6 13.♕a4 ♕b6 14.0-0 ♕xb2 15.♘bd2 ♗b5 is now well-known and considered acceptable for Black, as in the famous encounter Kramnik,V-Topalov,V Elista WCM (1st game) 2006.
A logical, but ugly move as Topalov decides to defend both b5 and c6. The alternative bishop development 10...♗a6 is possible, but 11.♘e5 ♘d5 12.♘xc6! ♘xc6 13.axb5 ♗xb5 14.♘xb5 leaves White with a pull due to his superior structure and a fine Catalan bishop.
White puts Black's structure under serious scrutiny.
Using the knight to hide his weaknesses.
Shifting the knight, but at the cost of temporarily reducing the bishop's influence along the diagonal.
12...♘b4 13.0-0 0-0 14.♖fd1
So far the moves seem to follow on naturally from Anand's novelty 10 ♘a3, so this position was probably still in the bounds of his preparation.
After 14...f6 Black may later have to worry about a slight loosening of his structure, but I can't be sure what Anand had in mind. it could have been 15.♘xd7 ♕xd7 16.♕e2 ♘8a6 17.d5 with pleasant activity for White.
The thematic way to exploit a lead in development in gambit lines in the Catalan as line opening should suit the better developed player.
Keeping things murky! Anand applies the principle of avoiding unnecessary exchanges when on the offensive. One can understand his thinking in that the obvious 16.♘xc6 ♘8xc6 17.dxc6 ♕xd2 18.♖xd2 doesn't seem to yield any advantage after 18...bxa4 19.♘xc4 ♗xc6.
Foreseeing that he will soon be able to capture on c4 with a knight.
17...♘8a6 18.dxc6 bxa4
Possible is 18...♗xc6 19.axb5 ♗xb5 when I can't see anything dramatic for White, however 20.♘axc4 ♗xc4 21.♖ac1 would leave White with a slight pull as White's minor pieces are likely to be superior to their black counterparts.
19.♘axc4 ♗xc6 20.♖ac1
Black has a nominal extra pawn (see the doubled a-pawns) and has made steps towards completing development, but White's forces are the better coordinated. So Anand can be fairly pleased about the result of his opening experiment.
A quiet little move with explosive consequences! Here 20...♕h5 is a lesser evil but, I must admit, I wouldn't feel particularly comfortable with Black's queen 'over there'.
Neglecting the kingside proves to be a fatal error of judgement.
Sacrificing a piece to prise open Black's king.
23...gxh6 24.♕xh6 f6
The only serious defence where Black's queen can be brought over to help out on the other wing. Now in order to exploit his initiative White needs to lift a rook over to the kingside.
The strongest follow-up, whereas 25.♗h3 ♕e7 26.♕g6+ ♔h8 27.♕h6+ is only drawn, and 27.♘f7+?? even loses, as after 27...♕xf7 28.♕xf7, the intermediate 28...♖xd1+ is check.
25...♗xg2 26.exf6 ♖xd6
Radical action, but eliminating White's minor pieces doesn't hold off the attack for long. Otherwise 26...♕h7 27.♕g5+ ♔h8 28.♖c4 leaves Black helpless in the face of ♖-h4.
27.♖xd6 ♗e4 28.♖xe6
Threatening the bishop as well as ♖-e7.
The plausible 28...♕h7 29.♕g5+ ♗g6 fails to the crushing 30.f7+!.
Black's threat to the f2-square only delays the inevitable. Now his kingside falls to pieces.
Spoilt for choice, White also has 30.♕g5+ ♔h8 31.♖xe4.
30...♕xf7 31.♖xe4 ♕f5 32.♖e7
White mates in five! i.e. 32...♖f7 33.♖c8+! ♕xc8 34.♕g6+ ♔h8 35.♕h5+ ♔g8 36.♕xf7+ ♔h8 37.♕g7#
A sensational display from 'Vishy'.
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