Indian chess ace Vishwanathan Anand settled old scores on Sunday when he beat World champion Ruslan Ponomariov of Ukraine to remain in the joint lead after the seventh round in the 65th Corus chess tournament in Wijk Aan Zee, The Netherlands.

Anand, who lost his World crown to Ponomariov last year, won in 34 moves.

Dutch champion Grandmaster Loek Van Wely defeated Jan Timman and continued to lead the table with Anand on 5 points.

However, the other overnight leader and world's highest rated woman, Judit Polgar, drew a tense game with top seeded Braingames champion Vladimir Kramnik and slipped to joint third spot on 4.5 points.

Joining her on the third spot was Spaniard Alexei Shirov, who humbled Evgeny Bareev of Russia.

In the Grandmaster 'B' tournament, former world junior girls' champion Koneru Humpy finally tasted success, cruising past local hope GM Harmen Jonkman.

Top seed GM Zhang Zhong recorded his sixth win on the trot, crushing GM Arkadij Naiditsch of Germany. The Chinese leads the field by a huge margin of 1.5 points, having 6.5 points in his kitty.

The Labourdonnais variation of the Sicilian has found few takers in elite chess circles for the past many years but Anand has not quite been an active advocate of the system. And he demonstrated precisely why with his white pieces yesterday.

Ponomariov continued with dangerous play and accepted a pawn sacrifice by Anand as early as on the 10th move. An alert Anand quickly developed his initiative and just five moves later the Ukrainian was fighting a lost battle.

Winning an exchange on the 17th move, Anand utilised all his pieces to perfection and penetrated the base rank with his rooks after the trade of queens.

Ponomariov lost another piece and fought on for a few moves in the hope of a miracle that did not happen. It took Anand just 34 moves to force resignation.

Loek Van Wely's in-depth preparation was again to the fore as he crushed his more famous rival easily. Playing black, Timman employed the Finachetto variation in the Slav defence and felt the heat right from the beginning.

Van Wely first got a space advatage with thematic manoeuvres and just while he threatened to roll his kingside pawns, Timman fumbled and found his king trapped in the middle of the board. The game lasted 24 moves.

Alexei Shirov gave an excellent display of attacking chess against Bareev, whose chances of defending the title have almost evaporated. Opting to take the poisoned pawn in French defence, Bareev went for unwarranted complications and was soon pushed to the wall by Shirov.

A temporary piece sacrifice on the 29th move by Shirov sealed Bareev's fate completely and he called it a day on the 28th move. The Spaniard won the public prize for best game of the day.

The fourth victor of the day was GM Alexander Grischuk of Russia, who scored his first win in the event defeating GM Michal Krasenkow of Poland. Playing white, Grischuk faced the Sicilian Sveshnikov and launched a direct attack after getting a tangible advantage in the ensuing middle gamKrasenkow succumbed to enormous pressure after 48 moves.

Kramnik troubled Polgar for a long time but in the end a virtuoso defence by the latter helped her salvage half a point from an evidently bad opposite colours Bishops endgame.

Former World champion Anatoly Karpov was again tested in defending a slight inferior position against Veselin Topalov.

From move 42 to 69, when the peace treaty was eventually signed, both just manoeuvred their pieces without a pawn move or any exchange taking place.

Ukrainian Vassily Ivanchuk did not budge and drew his seventh successive game of the tournament. The game against Teimour Radjabov of Azerbaijan lasted 22 moves, Ivanchuk's highest in last five games.

Results (round 7):

Vishwanathan Anand (5) beat Ruslan Ponomariov (Ukr, 2.5); Loek Van Wely (5, Ned) beat Jan Timman (Ned, 1.5); Alexei Shirov (Esp, 4.5) beat Evgeny Bareev (Rus, 3); Judit Polgar (Hun, 4.5) drew Vladimir Kramnik (Rus, 3.5); Alexander Grischuk (Rus, 4) beat Michal Krasenkow (Pol, 2.5); Veselin Topalov (Bul, 3.5) drew Anatoly Karpov (Rus, 3); Temiour Radjabov (Aze, 3) drew Vassily Ivanchuk (3.5).

Standings after round 7:

1-2 - Anand, Van Wely 5.0 each

3-4 - Polgar, Shirov 4.5 each

5 - Grischuk 4.0

6-8 - Ivanchuk, Kramnik, Topalov 3.5 each

9-11 - Karpov, Radjabov, Bareev 3.0 each

12-13 - Krasenkow, Ponomariov 2.5 each

14 - Timman 1.5.

B Tournament:

Zhang Zhong (Chn, 6.5) beat Arkadij Naiditsch (Ger, 4); Daniel Stellwagen (Ned, 5) drew Dennis De Vreugt (Ned, 4.5); Sergey Karjakin (Ukr, 4) beat Friso Nijboer (Ned, 4.5); Ian Rogers (Aus, 4) drew Jonny Hector (Swe, 4); John Van der Wiel (Ned, 2.5) drew Viktorija Cmilyte (Ltu, 1.5); Koneru Humpy (2.5) beat Harmen Jonkman (Ned, 2); Alexandra Kosteniuk (Rus, 2) beat Peter Acs (Hun, 2.5).

Standings after round 7: 1. Zhong 6.5; 2. Stellwagen 5.0; 3. Nijboer 4.5; 4-8. Karjakin, De Vreugt, Rogers, Hector, Naiditsch 4.0 each; 9-11. Acs, Van der Wiel, Humpy  2.5 each; 12-13. Kosteniuk, Jonkman 2.0 each; 14. Cmilyte 1.5.

The moves:

V Anand v/s Ruslan Ponomariov: 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nb5 d6 6. N1c3 a6 7. Na3 Nf6 8. Nc4 b5 9. Ne3 b4 10. Ncd5 Nxe4 11. a3 bxa3 12. Rxa3 g6 13. c3 Bd7 14. Nc4 Rb8 15. Be3 f5 16. Bb6 Rxb6 17. Ncxb6 Bh6 18. Bd3 O-O 19. Bxe4 fxe4 20. O-O Be6 21. Rxa6 Qh4 22. Qe2 Nd8 23. Ra8 Kg7 24. g3 Bg4 25. gxh4 Bxe2 26. Rfa1 g5 27. Nd7 Rf5 28. Rxd8 gxh4 29. Rg8+ Kf7 30. Ra7 Rf3 31. N7f6+ Ke6 32. Re7+ Kf5 33. Ng4 Bd2 34. Nge3+ black resigned.