CHESSBASE: CANDIDATES MATCH R4

Sofia R4: Kamsky strikes back – wins in 73 moves
21.02.2009 – Gata Kamsky used the white pieces in game four to grind down his opponent Veselin Topalov and equalise the score in the FIDE Candidates match in Sofia, Bulgaria. It was an impressive performance by the American GM, who thwarted Topalov's attempts to complicate the position and punished them when the Bulgarian went too far. GM commentary in English and Romanian.

The Kamsky-Topalov FIDE World Championship Qualifier is taking place from February 16th to 28th in the National Palace of Culture in Sofia, Bulgaria. The Match consists of eight games and if necessary tie-breaks. It has a prize find of US $250,000 which will be shared equally by the players. The winner qualifies for a World Championship Match against Viswanathan Anand, scheduled for later this year.

Round four report

Kamsky,G (2725) - Topalov,V (2796) [C92]
World Chess Challenge Sofia BUL (4), 21.02.2009 [Mihail Marin]

1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5.0-0 Be7 6.Re1 b5 7.Bb3 d6 8.c3 0-0

Topalov chooses a positional variation of the Ruy Lopez, which has not been part of his main repertoire with black so far. Despite the favourable result of the previous games, in which dynamic openings have been played, he may have felt that the Kamsky had won the theoretical dispute, which is a possible explanation for this change of scenario. 9.h3 Bb7. The so-called Zaitzev variation was aimed as an improved version of the Smyslow system which is characterized by the move order 9...h6 10.d4 Re8 11.Nbd2 Bf8 . The attack against the f7-square is not dangerous for Black, as practice has proved, which allows Black spare the move h7-h6. On the other hand, defining the light-squared bishop's intentions so soon adds force to White's plan of blocking the centre with d4-d5. 10.d4 Re8 11.Nbd2 Bf8 12.Ng5!? Over the past years, 12.d5 has become increasingly popular. The variation played by Kamsky is less common. 12...Re7 13.d5 Nb8 14.Nf1 Nbd7 15.Ng3 g6 16.Bc2 h6 17.Nf3 Nb6

The knight incursion to g5 has finally provoked the weakening of the black kingside with h7-h6, while the usefulness of the rook on e7 remains questionable. The strategic key to the evaluation of this position consists of the consequences of the pawn break c7-c6. This move would revive the b7-bishop but, weaken the d5-square and Black will obtain adequate play only if he manages to play d6-d5 under favourable consequences. 18.h4! This is a typical attacking move against the g6- and h6-pawns, but in this case it has a deeper strategical meaning. After the inevitable c7-c6, the pressure against the g6-pawn will make the further d6-d5 more difficult to carry out. 18...Qd7! The kingside structure seems to require the move 18...h5 , but this would allow White complete his development with gain of time. 19.Bg5 Bg7 Apparently, Black is doing absolutely fine, but White has a strong plan at his disposal. 20.Nd2! c6 21.Qf3 White will continue with dxc6, Nf1-e3, Rad1 and Bb3, which would put strong pressure over the d5-square. At the right moment, a sacrificial attack based on Nf5 could cause Black certain trouble. It may seem that Topalov's move is first of all aimed to meet h4-h5 with Qg4, safely defending the kingside. Actually, there is a lot more to say about this move. Black simply keeps developing and clears the eighth rank for the a8-rook. Later, the queen will be able to re-capture on c6 (after c7-c6, dxc6). 19.Nh2 Bg7 20.h5

20...Rf8! A strong prophylactic move, anticipating White's latent positional threat, hxg6. With a rook on f8, this exchange would just open the f-file for Black's counterplay. 21.Nhf1?! This move makes part of White's general plan, but he should also think about completing his developing. Kamsky may have thought that this aspect is less relevant, since the position is almost blocked. Given the excelent mobilisation of Black's forces, this static way of thinking is a bit dangerous. A natural reaction to the rook's departure from a8 would be 21.a4 , threatening to open the a-file or drive the b6-knight away from the control of the d5-square. The main drawback of this move is that it gives away the pair of bishops after 21...Nxa4 22.Bxa4 bxa4 23.Rxa4 , allowing Black obtain strong counterplay with 23...c6 24.c4 Nxh5 25.Nxh5 gxh5 26.Ra3 f5 when the rook's placement on f8 would be fully justified.; White could have countered Black's main plan with 21.Qf3 (Threatening Bxh6) 21...Kh7 22.b3 c6 23.Be3! and Black has to release some of the pressure against the d5-square. 21...c6 22.dxc6 Qxc6!? It seems more natural to capture with the bishop, but this move puts some indirect pressure against the white kingside and allows Black over-defend the g6-square in case of a further d6-d5. 23.Ne3

White has completed the first part of his regrouping, but this has cost him valuable time. Surprisingly, he is three whole tempi behind in development. 23...Kh7. Topalov approach in this stage of the game is too static. By slowly improving the placement of his pieces, he will allow Kamsky catch up with the development. It looks more logical to open the position at once with 23...d5 . 24.Qf3 Bc8 25.Rd1 Be6

26.b3! This move marks a radical change of the general course of the game. At the cost of a pawn, Kamsky restricts two of the pieces in which Black has invested most time, the e6-bishop and the b6-knight. Besides, the capture of the pawn will cost Black a few additional tempi. 26...Qxc3 27.Bd2 Qc7 28.Ba5 Qb8 29.Rd2 Nc8 30.Rad1. The situation has changed dramatically over the last moves. White has achieved a very harmonious development, while Black's coordination has deteriorated dramatically. 30...b4? This move weakens the b-pawn and the f1-a6 diagonal at the same time. White's task to prove a concrete attacking plan would have been more difficult if Black had just played a waiting move 31.Qe2 Kh8 32.Bd3 Na7 33.Rc1 Nb5 34.Bxb5 axb5 35.Bxb4

The material equality has been restablished and Black's position is in ruins. 35...Rd7 36.Rc6 Rfd8 37.Qd1 Bf8 38.Qc2 Kh7 39.Ba5 Re8 40.hxg6+ fxg6 41.Bc7 Qb7 42.Bxd6 Bf7 43.Bb4 Bxb4 44.Rxd7 Qxd7 45.Rxf6 Re6 46.Nd5 Bf8 47.Rf3 Kg7 48.Rc3 Ra6 49.Rc7 Qd6

White's position is almost perfect, with just one exception: his g3-knight is passive. There are two possible solutions to this problem. First of all, he could play Nf1-h2-g4, aiming to provoke h6-h5, in order to retreat to h2-f3. Kamsky chose a second way, deciding that the knight is useful on g3, by helping the queen to create threats against the enemy king. 50.Qe2. Threatening Qg4 followed by Nf5 and attacking the b5-pawn at the same time. 50...Kg8 51.Qxb5 Rxa2 52.Qb7 Ra1+ 53.Kh2 Bxd5 54.exd5. Since he will allow the exchange of queens anyway, 54.Qxd5+ would have been more stratightforward. 54...Qf6 55.Qc8. The move suggested by computers, 55.Kh3 is not easy to make in a practical game, with just 8 minutes left on the clock to reach the 60th move control. 55...Qh4+ 56.Qh3 Qxh3+ 57.Kxh3 Rd1 58.Ne4!

Black's position is hopeless. White has two strong passed pawns and a dominating knight. 58...Ba3 59.Ra7 Bb4 60.Rb7 Ba3 61.f3 Kf8 62.Rb5 h5 63.Kg3 Rc1 64.Rb8+ Kf7 65.Rb7+ Kf8 66.Kf2 Rc2+ 67.Kf1 Rc1+ 68.Ke2 Rc2+ 69.Kd3 Rxg2 70.Ra7 Be7 71.d6 Bd8 72.Nc5

72...Ke8? The final mistake. 72...Rg1 , threatening Rd1+, would have been more stubborn. WHite would probably have played 73.Ke4 Rd1 74.Kxe5 when Black's position would not have resisted for too long. 73.Rh7! White threatens to win the bishop with Rh8+ or create a mating net with Nf6 and d7. 1-0. [Click to replay]