1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.e3 After four games, we can notice a certain pattern in the players' match strategy. Kramnik sticks to the openings that enabled him take the lead (the Catalan with the black pieces and the Slav with Black), while Topalov deviates at a very early stage. Their attitude must have some psychological implications, because logically it is only Topalov who can be content about the outcome of the opening in the first two games.
4...e6 5.Nf3 Nbd7 6.Bd3 dxc4 7.Bxc4 b5 8.Bd3 Bb7 9.a3 [In the main lines starting with 9.0-0 ; or 9.e4 White has generally faced problems proving an advantage. By choosing a relatively unexplored line, Topalov shows that he does not intend to question Kramnik's famously accurate preparation and that he prefers to move the accent of the fight on the middlegame. This might be a reason why in the second game he refrained from his habitual 6.Ne5.]
9...b4 10.Ne4 Nxe4 11.Bxe4 bxa3 12.0-0 Bd6 [Another point behind Topalov's choice is that Kramnik had previously played 12...axb2 13.Bxb2 (Ivanchuk-Kramnik, New York rapid 1994). Although the game ended in a draw, accepting the pawn sacrifice at the cost of improving White's development looks quite risky. What is an acceptable choice for a rapid game does not necessarily suit a World Championship match.]
13.b3 [Much more ambitious than the immediate capture on a3. White intends to develop his bishop on the a3-f8 diagonal in order to control the important c5-square. Another interesting move here is 13.b4 as played in a couple of games.]
13...Nf6 14.Nd2 Typical for modern chess: even in rare lines, novelties occur at a relatively advanced stage of the game... Topalov rightly estimates that he does not need to retreat with the bishop, since the capture on e4 would lead Black with problems completing his development.
14...Qc7 [For instance, if 14...Nxe4 15.Nxe4 Bxh2+ 16.Kxh2 Qh4+ 17.Kg1 Qxe4 then 18.f3 followed by Bxa3 and Black cannot castle short any more.]
15.Bf3!? [Having failed to convince his opponent win a pawn on the queen side, White repeats the invitation on the opposite wing. The main alternatives are 15.Bxa3 ; and 15.h3 . By retreating the bishop to f3 (instead of d3 one move earlier) Topalov intends to keep the enemy queen side under pressure, in order to cause problems with carrying out the freeing move ...c5.]
15...Bxh2+ 16.Kh1 Bd6 17.Nc4 Be7 Kramnik's moving around with the bishop bears some similarity with the early queen incursions from his games with White. Black's position is quite solid and the extra-pawn offers compensation for the slight delay in development.
18.Bxa3 0-0 19.Bxe7 Qxe7 Black's extra pawn does not make itself felt yet and White's supremacy in the centre certainly offers him adequate play.
20.Ra5 In the previous games of the match, Topalov's play had generally focused towards the enemy king's castle. It happened in equal, in better and in worse positions and it proved quite effective up to a certain point. In the present game, the regroupment of the minor pieces suggested that he will mainly play on the queen side, but the last move is a clear hint that opposite wings communicate and that the queen side diversion could be just a prelude to a king side attack.
20...Rfd8 21.Kg1 The abstract idea behind this move is clear: before starting concrete action, White removes the king from a relatively exposed square. It is also some sort of proving that White is confident in his positional domination and that he doesnot need to rush up things in spite of being a pawn down.
21...c5!? Kramnik probably had enough of being submitted to long term pressure by his opponent in the first games of the match and uses the first given opportunity to free his position by returning the extra-pawn.
22.Rxc5 We can see here a point behind leaving the queen on d1 for one more tempo (instead of the natural 21.Qe2). The bishop is protected and White does not need to capture on b7 himself.
22...Ne4 23.Bxe4 Bxe4 24.Qg4 Bd3 25.Ra1 Rac8 26.Raa5 White's activity is impressive, but he cannot find targets in Black's position too easily. The next phase of the game might look a bit boring at a superficial glance, but contains many hidden nuances regarding the mutual interaction between the pieces.
26...Rb8 27.Qd1 Be4 28.Qa1 Rb7 29.Nd2 Bg6 30.Qc3 h6 31.Ra6 Kh7 32.Nc4 Be4 33.f3 Bd5 34.Nd2 Rdb8 35.Qd3+ f5 Finally, White has managed to induce a small weakness in the enemy structure, but this is a price Black is ready to pay for the stability of his centralized bishop.
36.Rc3 White will now try to occupy the centre with e4, which would offer him an advantage, but Black will defend very accurately.
36...Qh4 37.Ra1 Qg3 38.Qc2 Rf7 39.Rf1 Qg6 40.Qd3 Qg3 41.Rfc1 Rfb7 42.Qc2 Qg5 43.Ra1 [One of the nicest hidden lines from this phase is 43.e4? Bxb3! when the c1-rook would be hanging.]
43...Qf6 44.Qd3 Rd7 45.Ra4 Rbd8 46.Rc5 Kg8 47.Nc4 Bxc4 48.Raxc4 f4 White cannot avoid complete the complete simplification of the position now.
49.Rc6 fxe3 50.Qxe3 Rxd4 51.Rxe6 Qh4 52.Rxd4 Qxd4 53.Re8+ Kh7 54.Qxd4 Even according to the Sofia rule the position should be considered a dead draw. 1/2-1/2