Home favourite Veselin Topalov shocked Viswanathan Anand [Images] in a brilliant and aggressive display in the sixth round that had the fans on the edge of their seats through the four hours.

It also earned for Topalov, the home favourite his first win, and for Anand it was his first defeat. It was Anand's first loss to Topalov since Corus 2004.

In another game, Ruslan Ponomariov defeated Vladimir Kramnik [Images], who blundered during his game and never really recovered. Pono, the former FIDE champion, did not let go the chance, and grabbed it with both hands for his second straight win in the tournament.

Kramnik resigned on the 45^th move after the game began in the Queen's Indian. Kramnik now has two wins and two losses and two draws in six rounds.

In the third game, Judit Polgar got an edge against Michael Adams after the latter erred while trying for a win. It was Adams who looked better at the start and then started caving in a game that began in Petroff defence. Adams was the leader after five rounds with three points and is now tied second with Polgar, Kramnik and Topalov. Ponomariov is the new leader with 3.5 points, while Anand has 2.5 points.

Anand is the only player still looking for his first win, while Ponomariov and Kramnik have two wins each. Polgar, Topalov and Adams have registered one win each. Kramnik has produced most results with two wins, two losses and two draws. After Anand's loss no player remains unbeaten.

The Topalov-Anand game began in the Queen's Indian and it lasted 52 moves. Topalov made a knight sacrifice early on and then gave an exchange, but all this while he was going all out on attack. As the game progressed he not only got the piece back, but had Anand on the back foot, resulting in Topalov having a Knight, Bishop and three pawns to Anand's rook and one pawn. Anand kept hanging on hoping for some let-up from Topalov but it never came and he ultimately resigned.

Ponomariov cracked his second successive win beating Kramnik on another board after another Queen's Indian opening. Ponomariov's win put him at 3.5 points from six games and in the leader's position, where he could be joined by Michael Adams should he draw the game against Judit Polgar.

Anand may have lost the sixth round, but he has doubtlessly been engaged in a thrilling game in each of his six rounds. But then so has been Topalov, despite his defeat at the hands of Ponomariov in the fifth round.

Topalov admitted that he was not too happy after his loss to Ponomariov, but then added, "The simultaneous display on the rest day improved my mood and it showed."

Also Read Anand held to fifth successive draw Anand draws with Polgar Anand draws with Ponomariov Anand draws with Kramnik Anand, Topalov in thrilling draw

Ponomariov, who was at one point in the last position, is now the leader. Anand, when asked about the turnaround in the tournament situation, said, "The results of the last two rounds explain that." He was referring to the two wins by Ponomariov and his two draws, as also Kramnik's loss to Ponomariov.

Anand, who said just relaxed on the rest day while Topalov played a simultaneous, added, "I hope the tournament situation changes for me like it has for some others. All I can say I am looking forward to the next few games."

Topalov sacrificed a knight as early as the 14^th game after staring out from the Queen's Indian defence. Topalov with his 4.g3 contested control of the long white diagonal. That started as a positional-cum-strategic tussle as Anand decided to attack white's c-pawn.

This was one time Anand took his time while playing. He spent nearly 23 minutes before his 16. ..Bc8. Topalov playing ultra-aggressive offered an exchange on the 18^th move, which Anand did not take immediately. Ultimately Anand went a full piece up, but later when under fire, he had to return it. After trying for long, Anand finally forced an exchange of queens, which he had attempted as far back as the 20^th by playing b5.

Into the endgame, Topalov emerged a pawn up and then gradually built it to Knight and bishop versus Rook plus a huge pawn advantage for the Bulgarian. Anand finally resigned on the 53^rd move to call it a day.

Topalov � Anand

Queen's Indian

1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. g3 Ba6 5. b3 Bb4+ 6. Bd2 Be7 7. Nc3 c6 8. e4 d5 9. Qc2 dxe4 10. Nxe4 Bb7 11. Neg5 c5 12. 12. d5 exd5 13. cxd5 h6 14. Nxf7 Kxf7 15. O-O-O Bd6 16. Nh4 Bc8 17. Re1 Na6 18. Re6 Nb4 19. 19. Bxb4 cxb4 20. Bc4 b5 21. Bxb5 Be7 22. Ng6 Nxd5 23. Re7+ Ne7 24. Bc4 Kf6 25. Nxh8 Qd4 26. Rd1 Qa1+ 27. Kd2 Qd4+ 28. Ke1 Qe5 29. Qe2 Qxe2 30. Kxe2 Nf5 31. Nf7 a5 32. g4 Nh4 33. h3 Ra7 34. Rd6 Ke7 35. Rb6 Rc7 36. Ne5 Ng2 37. Ng6 Kd8 38. Kf1 Bb7 39. Rxb7 Rxb7 40. Kxg2 Rd7 41. Nf8 Rd2 42. Ne6+ Ke7 43. Ng7 Rxa2 44. Nf5+ Kf6 45. Nxh6 Rc2 46. Bf7 Rc3 47. f4 a4 48. bxa4 b3 49. g5+ Kg7 50. f5 b2 51. f6 Kh7 52. Nf5 Black resigns

Pairings for seventh round on Thursday: Polgar v Ponomariov; Adams v Topalov; Anand v Kramnik

Points after sixth round: 1. Ponomariov 3.5; 2. Adams 3 plus one game); 3. Topalov and Kramnik (3); 4. Anand 2.5 points; Polgar (2 plus one game)

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