Kolkata, Sep 2 - International Master Himanshu Sharma and Vidit Santosh Gujrathi caused major upsets by scalping highly rated Grandmasters in the second round of the fourth Kolkata Open Grandmaster Chess Tournament here Wednesday.

Himanshu defeated Grandmaster Viktor Laznicka (2634) of the Czech Republic in 61 moves of a Sicilian defence game. Himanshu had a better pawn structure which allowed him to win a pawn and he converted this advantage into victory with a splendid endgame.

Gujrathi accounted for Indian Grandmaster G.N. Gopal in 50 moves. The FIDE Master won a couple of pawns on the queenside and forced his opponent to resign to on the Gorky Sadan table.

International Master Sriram Jha pushed top seeded Grandmaster Shakhriyar Mamedyarov of Azerbaijan into a draw while Deep Sengupta split point with another Azerbaijan Grandmaster Gadir Gusenov.

International Master B.Adhiban of India held highly rated Grandmaster Aleksej Aleksandrov of Belarus from the white side of a four knight's game. Adhiban held the advantage for most of the game and had a better position when the Belarussian Grandmaster repeated moves to get the draw on the 51st move.

All three International Masters Himanshu, Deep and Adhiban are candidates for GM norms in this tournament.

Grandmaster Surya Sekhar Ganguly was at his irrepressible best in the second round, against double Gm norm holder and International Master R.R. Laxman. The IM messed up the move order in a Petroff defence and was punished quickly. Ganguly sacrificed a Bishop on the fourteenth turn to open up his opponent's kingside and Laxman resigned a couple of moves later.

Local U-12 World Champion Sayantan Das caused a flutter when he defeated International Master S.P. Sethuraman.

Important results :

IM Sriram Jha(1.