Grandmaster P Harikrishna scored significant win over Sergei Tiviakov in the eighth round of the Montreal International Chess tournament.

Harikrishna now occupies the second position along with Tiviakov, half-a-point behind Vassily Ivanchuk of Ukraine.

It was an exciting day in the tournament as four of the five games ended decisively and Ivanchuk made the most of Tiviakov's loss by shooting into the lead with a win against GM Kamil Miton with the black pieces.

GM Nigel Short overcame his abysmal form to register his first victory of the tournament by beating Pavel Eljanov while Gata Kamsky fell back to the fourth position when he drew his game against Pascal Chabonneau.

Mark Bluvshtein crashed to his fourth successive defeat, losing to Emil Sutovsky in the eighth round.

Harikrishna played the Fianchetto Variation against the Queens Indian defense and got a minute edge from the opening.

The players waged a slow strategic battle and the game seemed to be heading for a draw after the queens were exchanged on the 28th move. Tiviakov tried to seize the initiative by advancing his kingside pawns at the cost of creating weakness in his position.

Harikrishna made inroads into the black position by exploiting this factor and obtained the better prospects in the endgame. He won a pawn with a nice tactical shot on the 50th move and then nursed his advantage to victory with precise technical play.

Ivanchuk scored a superb victory over Polish GM Kamil Miton and emerged sole leader. Playing the Queens Indian Defense, Ivanchuk equalised without much difficulty after the exchange of light squared bishops.

Miton tried to attack on the queenside but Ivanchuk easily parried the threats. The focus of the game suddenly shifted to the kingside when Ivanchuk sacrificed a bishop to rip open the white king's position.

Miton was unable to cope with the threats to his king and suffered huge material loss. He resigned in a completely hopeless position after 40 moves.

The game between Kamsky and Charbonneau was a hard-fought technical tussle. Kamsky, playing black, tried his best to complicate matters after drifting into a worse endgame, but all his inventiveness could not fetch him more than a draw.

Short demonstrated excellent tactical play to beat Pavel Eljanov with the black pieces. Mark Bluvshtein, who had played so well in the initial rounds, seemed all at sea against the Tarrasch defense employed by Israeli GM Emil Sutovsky.

Having got into an inferior position in the endgame, Bluvshtein failed to put up much resistance and went down in 40 moves.

Results 

Round 8: Kamil Miton (Pol, 3.5) lost to Vassily Ivanchuk(Ukr, 6.0); Pentala Harikrishna (Ind, 5.5) beat Sergei Tiviakov (Ned, 5.5); Pascal Charbonneau (Can, 2.5) drew Gata Kamsky (USA, 5.0); Pavel Eljanov (Ukr, 4.0) lost to Nigel Short (Eng, 2.0); Mark Bluvshtein (Can, 2.5) last to Emil Sutovsky (Isr, 3.5)

The moves - P. Harikrishna  vs S. Tiviakov
1.d4 Nf6 2.c4 e6 3.Nf3 b6 4.g3 Bb7 5.Bg2 Be7 6.Nc3 Na6 7.00 00 8.Bf4 Ne4 9.Nxe4 Bxe4 10.Qa4 Qc8 11.Ne5 Bxg2 12.Kxg2 f6 13.Nf3 c5 14.Rfd1 Rf7 15.dxc5 Nxc5 16.Qc2 Qb7 17.Be3 Rc8 18.Rac1 Ne4 19.Kg1 Bc5 20.Qb3 h6 21.Bxc5 Rxc5 22.Rd4 f5 23.Rcd1 Qc7 24.Qe3 Re7 25.b3 Nf6 26.Nh4 Kf7 27.Qf3 Qc6 28.Qxc6 Rxc6 29.Nf3 e5 30.R4d2 Ke6 31.Nh4 g5 32.Ng2 f4 33.f3 d6 34.gxf4 gxf4 35.e3 fxe3 36.Nxe3 Rg7+ 37.Kh1 Ne8 38.Nd5 Kd7 39.Re2 Rc8 40.a4 Rf7 41.Rd3 Ng7 42.Nc3 Kc6 43.Rg2 Re8 44.b4 Re6 45.b5+ Kb7 46.a5 bxa5 47.Ne4 Nf5 48.c5 d5 49.Rxd5 Ne3 50.Rd6 Ree7 51.Re2 Nf5 52.Ra6 Kb8 53.Rxa5 Rd7 54.Ra1 Nd4 55.Rg2 Nxb5 56.Rb2 Rb7 57.c6 Rb6 58.Rxb5 Rxb5 59.Nd6 Rf6 60.Nxb5 Rxc6 61.Nxa7 Rc5 62.Kg2 Kb7 63.Kg3 Kb6 64.Kg4 Kb7 65.Kf5 h5 66.Ra4 Kb6 67.h4 Kb7 68.Re4 Kxa7 69.Rxe5 Rc3 70.f4 Rg3 71.Ke6 Rg6+ 72.Kf7 Rg4 73.f5 Rxh4 74.f6 Rh1 75.Ke6 h4 76.f7 Rf1 77.Rf5 10. Black resigns.

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