World Cup champion Vishwanathan Anand regained the joint lead after a crushing victory over former world champion Anatoly Karpov of Russia in the fifth round of 65th Corus chess tournament in Wijk Aan Zee, the Netherlands, on Thursday.

Latvia-born Spaniard Alexei Shirov ripped apart the defences of Braingames champion Vladimir Kramnik of Russia and joined Anand and the world's best woman player Judit Polgar at the top of the table on 3.5 points.

Following the three leaders are Dutch GM Loek Van Wely and defending champion Evgeny Bareev of Russia on 3 points each while Kramnik, GM Vassily Ivanchuk of Ukraine and GM Alexander Grischuk of Russia trail them by half a point.

In the Grandmaster "B" tournament, former world junior girls' champion Koneru Humpy suffered another defeat, outsmarted by top seed Grandmaster Zhang Zhong of China in a long-drawn game.

Zhong (4.5 points) maintained his sole lead with the victory. The high point of this section was the victory of 15-year-old local hope Daniel Stellwagen, who beat GM Arkadij Naiditsch of Germany.

An International Master, Stellwagen is now strongly gunning for a Grandmaster norm in the event, having tallied 4 points.

Anand has played more than 80 games against Karpov in various tournaments and holds a plus score against the legendary player. Yesterday too, the Indian ace did not disappoint his fans, playing an exciting game.

Playing white, Anand opened with the king pawn in the sharpest advance variation and faced the Caro Kann that has been serving Karpov well. The middle game was full-bloodied as Karpov sacrificed a piece for three pawns in the initial stage and threatened to roll down the pawns with Anand's King left in an open position.

Once the dust settled down a bit, Anand made steady but definite progress on both flanks. On the 27th move the Queens got traded and thereafter Anand gave little respite to Karpov.

On the 44th move, Karpov finally called it a day.

Anand's brilliant victory was overshadowed to some extent by Shirov's triumph over Vladimir Kramnik for whom this was the second loss in the event, having gone down to World champion Ruslan Ponomariov of Ukraine in the second round.

Kramnik has, in fact, had most number of decisive games so far, with two victories and two losses.

Shirov is the only player in the world who has troubled Kramnik repeatedly with his magical tactical abilities and he proved it yet again. With white, Shirov faced the Sicilian Sveshnikov that has been revived a great deal by Kramnik himself in the past few years.

Kramnik came out of the opening with a dynamically balanced middle game. But as the game progressed the Russian missed the thread of the position, blundered a pawn and lost rather tamely in the end. This game too lasted till the 44th move.

Loek Van Wely accounted for Bulagrian GM Veselin Topalov in an astonishing manner. The Closed structure against the Sicilian gave Topalov, white, a slight advantage as he held firm control in the centre.

Van Wely kept himself much in the game with right deployment of pieces on the kingside and when Topalov went astray by avoiding a forced drawing sequence, he struck hard to create decisive mating threats. Topalov resigned after 37 moves.

The youngest participant in the fray, Teimour Radjabov of Azerbaijan got the better of Dutchman Jan Timman, who misplayed a roughly level endgame.

The white pieces gave Radjabov some initiative after the opening moves of a Queen's Indian defence but Timman sorted out his problems with routine exchanges. However, on the 35th move Timman worked on an illusionary attack and sacrificed his knight for just one pawn. Radjabov defended well to register his first victory in the event in 54 moves.

Overnight leader Judit Polgar achieved nothing with her white pieces against Ivanchuk and took a draw in the middle game out of an English opening by transposition.

Grischuk drew a well-contested game against Ponomariov.

The other game between Polish GM Michal Krasenkow and Bareev also finished in a draw.

Results: Alexei Shirov (Esp, 3.5) beat Vladimir Kramnik (Rus, 2.5); Judit Polgar (Hun, 3.5) drew Vassily Ivanchuk (Ukr, 2.5); Vishwanathan Anand (3.5) beat Anatoly Karpov (Rus, 2); Alexander Grischuk (Rus, 2.5) drew Ruslan Ponomariov (Ukr, 2); Veselin Topalov (Bul, 2) lost to Loek Van Wely (Ned, 3); Teimour Radjabov (Aze, 2) beat Jan Timman (Ned, 1.5); Michal Krasenkow (Pol, 1.5) drew Evgeny Bareev (Rus, 3).

Standings after Round 5: 1-3. Shirov, Anand, Polgar 3.5 each; 4-5 Van Wely, Bareev 3.0 each; 6-8. Ivanchuk, Kramnik, Grischuk 2.5 each; 9-12. Topalov, Radjabov, Karpov, Ponomariov 2.0 each; 13-14. Timman, Krasenkow 1.5 each.

B Tournament:

Zhang Zhong (Chn, 4.5) beat Koneru Humpy (1.5); Daniel Stellwagen (Ned, 4) beat Arkadij Naiditsch (Ger, 3); Ian Rogers (Aus, 3) drew Friso Nijboer (Ned, 3.5); Sergey Karjakin (Ukr, 2.5) drew Peter Acs (Hun, 2); John Van der Wiel (Ned, 2) drew Dennis De Vreugt (Ned, 3); Alexandra Kosteniuk (Rus, 1) lost to Harmen Jonkman (Ned, 2); Viktorija Cmilyte (Ltu, 0.5) lost to Jonny Hector (Swe, 2.5).

Standings after Round 5: 1. Zhang Zhong 4.5; 2. Stellwagen 4.0; 3. Nijboer 3.5; 4-6. Rogers, De Vreugt, Naiditsch 3.0 each; 7-8. Karjakin, Hector 2.5 each; 9-11. Van der Wiel, Acs, Jonkman 2.0 each; 12. Humpy 1.5; 13. Kosteniuk 1.0; 14. Cmilyte 0.5.

Moves:

Viswanathan Anand v/s Anatoly Karpov: 1. e4 c6 2. d4 d5 3. e5 Bf5 4. Nc3 e6 5. g4 Bg6 6. Nge2 Ne7 7. f4 c5 8. Ng3 cxd4 9. Nb5 Nec6 10. f5 Bc5 11. Nd6+ Bxd6 12. exd6 Qxd6 13. Bg2 f6 14. fxg6 hxg6 15. O-O Nd7 16. Rf2 O-O-O 17. c3 dxc3 18. bxc3 Nb6 19. Nf1 Rd7 20. h3 f5 21. Rb1 Rf8 22. Qb3 Rff7 23. Qc2 Rc7 24. Qd3 Na4 25. Bf4 e5 26. Bh2 f4 27. Qxd5 Qxd5 28. Bxd5 Rfe7 29. c4 Nd4 30. Nd2 Nc3 31. Re1 b5 32. Ne4 Nxe4 33. Rxe4 g5 34. cxb5 Nxb5 35. Re1 Nc3 36. Bb3 a5 37. Kf1 a4 38 Bc2 Kb7 39. Bf5 a3 40. Rc2 Rc6 41. Bg1 Rc4 42. Bf2 e4 43. Rec1 Rec7 44. Be1 black resigned.

Alexei Shirov v/s Vladimir Kramnik: 1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 e5 6. Ndb5 d6 7. Bg5 a6 8. Na3 b5 9. Bxf6 gxf6 10. Nd5 f5 11. Bd3 Be6 12. O-O Bxd5 13. exd5 Ne7 14. c3 Bg7 15. Qh5 e4 16. Bc2 O-O 17. Rae1 Qc8 18. Bb3 a5 19. Qg5Qb7 20. f3 h6 21. Qg3 a4 22. Bc2 b4 23. Nc4 Qxd5 24. fxe4 Qxc4 25. exf5 Nd5 26. f6 Nxf6 27. Rxf6 Rae8 28. Ref1 Re2 29. Bd3 Qc5+ 30. Kh1 Re3 31. R6f3 Rxf3 32. Qxf3bxc3 33. bxc3 Qe5 34. c4 Kh8 35. Bc2 Qa5 36. Qd3 f5 37. Qxd6 Qc3 38. Bd3 Qd2 39. c5 Qxa2 40. c6 Rg8 41. Qg6 Rf8 42. c7 Qg8 43. Qc6 Rc8 44. Ba6 black resigned.

Veselin Topalov v/s Loek Van Wely: 1. e4 c5 2. Nf3 Nc6 3. Nc3 e5 4. Bc4 Be7 5. d3 d6 6. O-O Nf6 7. Ng5 O-O 8. f4 exf4 9. Bxf4 Na5 10. Qd2 Nxc4 11. dxc4 Bg4 12. Nf3 Re8 13. Qf2 Qb6 14. b3 Bh5 15. Rae1 Qc6 16. h3 Rad8 17. Nh4 Bg6 18. Nxg6 fxg6 19. Qf3 h6 20. Nd5 Kh7 21. Bd2 Qd7 22. Nf4 g5 23. Ne2 Rf8 24. Qd3 g6 25. Nc3 Qe6 26. Nd5 Nd7 27. Nc7 Qg8 28. Bc3 Bf6 29. Bxf6 Rxf6 30. Qd5 b6 31. Qb7 Qg7 32. Qxa7 Rdf8 33. Nb5 R8f7 34. Qc7 g4 35. hxg4 Ne5 36. Qxb6 Nxg4 37. e5 Rxf1+ white resigned.