Pendalya Harikrishna split the point with Canada's Pascal Charbonneau after a game of fluctuating fortunes and slipped to tied third place after the seventh round in the eighth Montreal International Chess Tournament.
The Indian shares third place with American GM Gata Kamsky.
Harikrishna adopted the Queen's Gambit, which was declined by Charbonneau, who took the initiative with some sharp moves in the opening. He sacrificed a pawn in the early middle game and obtained excellent compensation by exposing his opponent's castled King.
He continued to improve his position and was in with a good winning chance but the game took a dramatic turn on the 26th move when he blundered away a bishop.
Charbonneau returned the favour by blundering on the 40th move and allowed material parity. The resulting position was clearly drawn and the players signed peace after the 42nd move.
Meanwhile, Dutch Grandmaster Sergei Tiviakov continued his brilliant form and remained sole leader after beating Polish Grandmaster Kamil Miton.
GM Vassily Ivanchuk improved his standing in the tournament and moved to second place after a victory over GM Mark Bluvshtein of Canada.
Ivanchuk gave a superb display to easily outplay Mark Bluvshtein. Playing the Ritcher Rauzer attack against the Sicilian, Ivanchuk won a pawn with some brilliant tactics.
A queen ending was reached after the middle game complications were over. Ivanchuk demonstrated fluent technique in the endgame to win in 54 moves.
Grandmaster Sergei Tiviakov was a little lucky to remain in the lead as he managed to beat Kamil Milton after getting into a worse position in the middle game.
The game between Nigel Short and Gata Kamsky was hard-fought with neither player being able to get the upper hand. The players agreed to a draw in rook and bishop endgame after 45 moves.
Emil Sutovsky and Pavel Eljanov chose to play it safe and agreed to split the point in just 17 moves after some quiet opening play.
Results Round 7:
Sergei Tiviakov (Ned, 5.5) beat Kamil Miton (Pol, 3.5); Vassily Ivanchuk (Ukr, 5.0) beat Mark Bluvshtein (Can, 2.5); Pendyala Harikrishna (Ind, 4.5) drew Pascal Charbonneau (Can, 2.0); Nigel Short (Eng, 1.0) drew Gata Kamsky (USA, 4.5); Emil Sutovsky (Isr, 2.5) drew Pavel Eljanov (Ukr, 4.0).
P Harikrishna vs P Charbonneau
1.d4 Nf6 2.Nf3 d5 3.c4 e6 4.Nc3 Be7 5.Bf4 00 6.e3 c5 7.dxc5 Bxc5 8.cxd5 Nxd5 9.Nxd5 exd5 10.Bd3 Bb4+ 11.Nd2 Nc6 12.00 d4 13.e4 f5 14.a3 Ba5 15.b4 fxe4 16.Bxe4 Rxf4 17.bxa5 Nxa5 18.Qc2 h6 19.Rfe1 Bg4 20.f3 Bh5 21.Rac1 Rf8 22.Qc5 Bf7 23.Qf5 g6 24.Qf4 h5 25.Qg3 d3 26.Bxg6 Qb6+ 27.Kf1 Qxg6 28.Qh4 Nb3 29.Nxb3 Bxb3 30.Rc5 Rf5 31.Rxf5 Qxf5 32.Qg3+ Kh8 33.Qd6 Bf7 34.Qd4+ Kh7 35.Re5 Qg6 36.g4 hxg4 37.Re4 Be6 38.Rf4 Kg8 39.Ke1 Qg5 40.Qe3 Re8 41.Rf8+ Kxf8 42.Qxg5 gxf3 . Draw agreed.