Grandmaster P Harikrishna went down fighting against GM Alexander Grischuk of Russia [Images] in the fourth round of Aerosvit International Grandmasters chess tournament in Crimea.

The loss put Harikrishna in a spot of bother in the category-18 round-robin event as the Indian remained on 1.5 points from four games and slipped to joint eighth.

It turned out to be another exciting day as three out of six games ended decisively.

Interestingly, all the victories in the fourth round were scored by players with black pieces which is quite unusual in such a high category event.

Gaining ground was former World championship finalist Vassily Ivanchuk of Ukraine, who scored a tremendous victory over tournament leader Shakhriyar Mamedyarov of Azerbaijan.

The other winner of the round was Russian champion Sergei Rublevsky, who scored his second victory on the trot after accounting for 2005 European champion Liviu-Dieter Nisipeanu of Romania.

With seven rounds still to come, Grandmaster Viktor Bologan of Moldova emerged as the sole leader on three points after drawing his fourth round game with Andrei Volokitin of Ukraine.

Trailing the leader by a half point is a pack of six players -- Ivanchuk, Mamedyarov, Grischuk, Volokitin, Rublevsky and Grandmaster Alexei Shirov of Spain, who all have 2.5 points each in their kitty while Harikrishna is in joint eighth spot now on 1.5 points along with Alexander Areshchenko of Ukraine.

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