Grandmasters Dibyendu Barua and Sandipan Chanda suffered their second defeat of the championship as overnight joint leaders, Pavel Kotsur of Kazakhstan and Saidali Iuldachev of Uzbekistan, maintained their top position in the Parsvanath International Chess tournament at New Delhi on Sunday.

Barua and Chanda, who had lost to Nassir Wajih and International Master Atanu Lahiri respectively in the third round, failed to challenge their higher rated opponents in the seventh round of the championship.

Barua, the top ranked Indian in the tournament, was made to bite the dust by top seed Kotsur while Chanda went down to Iuldachev to slip to joint fourth position.

Kotsur and Iuldachev, with 6.5 points each, are half a point adrift of four players - GM Serik Temirbaev of Kazakhstan, IM R Balasubramanium, IM D V Prasad and C S Gokhale - in the second spot.

The top board game between Kotsur and Barua failed to live up to the expectations as the former took full advantage of the lapses made by the Indian.

Opting for a Slav defence, Barua was in a better position but some hasty moves in the middle game saw him lose the initiative.

The Kazakh took control of the tie by the 24th move forcing Barua to surrender in 32 moves.

Chanda opened with the king pawn and allowed Iuldachev to gain a level position. The middle game was keenly contested with the Uzbek taking control and he took advantage of a slightly favourable rook and pawn ending to win.

International Masters Chandra Shekhar Gokhale and D V Prasad defended their second position beating Mohammed Javed Woman Grandmaster Arthie Ramaswamy respectively.

Prasad, playing black, resorted to an attacking game as he penetrated to the centre to take command with the queen and then exchanged it with a pawn in a Sicilian Paulsen variation game. 

GMs Surya Shekhar Ganguly, R B Ramesh, Koneru Humpy and Safit Sukhrat of Uzbekistan also took a full point lead while Lahiri, N Sudhakar Babu and Dronavalli Harika remained disappointed with no gains.

Important Results (Round-7):

Pavel Kotsur (Kaz, 6.5) bt Dibyendu Barua (5); Sandipan Chanda (5) lost to Saidali Iuldachev (Uzb, 6.5); Abhijeet Gupta (0) lost to Serik Temirbaev (6, Kaz); Sriram Jha (5.5) drew Neeraj K Mishra (5.5); R R Laxman (5.5) drew Tejas Bakre (5.5); Aranu Lahiri (5) lost to R Balasubranium (6); Aathie Ramaswamy lost (5) to D V Prasad (6); C S Gokhale (6) bt Md Javed (5); S S Ganguly (5.5) bt Suvrajit Saha (4.5); Deep Sengupta (4.5) lost to Safi Sukhrat (5.5); S Poobesh Anand (4.5) bt R B Ramesh (5.5); N Sudhakar Babu lost to Nurlan Ibraev (Kaz, 5.5); Dronavalli Harika (4.5) lost to M R Venkatesh; Abdul Maleq (4) lost to Koneru Humpy (5).