Grandmaster Krishnan Sasikiran delivered a vital blow to English GM Michael Adams in the sixth round to jump in joint lead in the 3rd Mtel Masters Chess tournament in Sofia, Bulgaria.

Playing white Sasikiran punished Adams for his inaccuracy in the middle game and romped home in quick time on a day that witnessed all decisive games and the leaders on the receiving end.

Sasikiran used his white pieces effectively in a Queen's Indian defence game and won in 34 moves.

Apart from Adams who was sole second before the start of 6th round, tournament leader Grandmaster Shakhriyar Mamedyarov suffered a shock defeat at the hands of tail ender Gata Kamsky of United States while former world champion Veselin Topalov of Bulgaria continued with his winning ways and downed Liviu-dieter Nisipeanu of Romania in the other game of the day.

As things stand, Sasikiran and Mamedyarov share the lead on 3.5 points out of a possible six while Adams is now sharing the third spot on 3 points with Topalov. Nisipeanu and Kamsky are now at the bottom on 2.5 points each.

Results round 6: Krishnan Sasikiran (Ind, 3.5) beat Michael Adams (Eng, 3); Liviu-Dieter Nisipeanu (Rom, 2.5) lost to Veselin Topalov (Bul, 2.5); Gata Kamsky (1.5) beat Shakhriyar Mamedyarov (Aze, 3.5).

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