White: Sergey Volkov
Black: Mark Hebden
Round 4
Kings Indian E923
1 d4 Nf6 2 c4 g6 3 Nc3 Bg7 4 e4 d6 5 Be2 0-0 6 Nf3 e5 7 Be3 Ng4 8 Bg5 f6 9 Bh4 Nc6 10 d5 Ne7 11 Nd2 Nh6 12 f3 c5 13 dxc6 bxc6 14 b4 Kh8 15 Nb3 g5 16 Bf2 f5 17 Qd2
According to Hebden, 17 0-0 is White's normal choice here. 17...fxe4!? Preparing a pawn sacrifice.
18 Nxe4 d5 19 Nxg5 Ng6 20 g3 e4 21 0-0?
After the game Volkov criticised this choice, preferring 21 Rd1 instead. Black still has compensation after 21...exf3 22 Nxf3 Bg4, but this is certainly what White should have gone for.
21...exf3 22 Bxf3 Ne5!
Perhaps Volkov missed the strength of this move. On the other hand 22...Bxa1? 23 Rxa1 would leave the black king very short of cover.
23 Bd4 dxc4 24 Rad1
Perhaps 24 Bxe5 Bxe5 25 Rad1 is stronger.
24...cxb3 25 Bxe5 Qb6+ 26 Bd4 Qxd4+ 27 Qxd4 Bxd4+ 28 Rxd4 bxa2 29 Rh4?
White should try 29 Ra1, but Black is still better after Hebden's suggested continuation of 29…Nf5 30 Rf4 h6 31 Ne4 Be6 32 Nc3 Nd4.
29...a5!
The winning move.
30 b5
After 30 Rxh6 axb4 the Black pawns are just too strong. The rest of the game is reasonably straightforward for the English GM.
30...Bg4 31 Rxh6 Bxf3 32 Ra1 cxb5 33 Rxa2 Bd5 34 Rd2 Rf5 35 h4 a4 36 Re2 Kg8 37 g4 Rxg5! 38 hxg5 a3 39 Re1 a2 40 Ra1 Ra4 41 Kf2 Rxg4 42 Rd6 Rxg5 43 Rxd5 Rxd5 44 Rxa2 Kf7 45 Ra6 Rf5+ 46 Ke3 Rf6 47 Ra7+ Kg6 48 Rb7 Rf5 49 Ke4 h5 50 Rb8 Rc5 51 Kd4 Rg5 52 Rb6+ Kf7 53 Rb7+ Ke6 54 Rb6+ Kd7 55 Rh6 b4 56 Kd3 Ke7 57 Kc2 Kf7 58 Kb3 Kg7 59 Rd6 Rg4 60 Rc6 Rd4 0-1