Former World champion Viswanathan Anand suffered a shock defeat against 16-year-old Grandmaster Teimour Radjabov of Azerbaijan in the second round of the Dortmund Sparkassen chess meeting in Dortmund, Germany.
In another match, top seed and World No. 2 Vladimir Kramnik of Russia settled for a truce against Viktor Bologan of Moldova to remain in joint lead with Bologan, tallying 1.5 points out after two rounds.
Peter Leko of Hungary also drew his game with local hope Arkadi Naiditsch in a keenly-contested game and remained on a 50 per cent score, having drawn the first game with Anand.
For Naiditsch and Radjabov, it was their first points on the board in this category 18 tournament.
Radjabov, who beat Garry Kasparov of Russia in the Linares tournament in Spain earlier this year, became the first player to beat both Kasparov and Anand in classicial chess with black pieces in the same year.
The chess sensation from Baku showed his tactical brilliance yet again and pounced on his chances just when everyone thought Anand would cruise through with white.
Anand, who won the Corus Chess tournament this year, showed little signs of improving his record at Dortmund where he finished at the bottom of the pack in his last outing in 2001.
The Indian wizard was in trouble right through, missing out on a number of chances.
Anand opened with the king pawn and faced yet another Sicilian defence. Radjabov employed the accelerated Sveshnikov that might have come as a big surprise for Anand. In the first round against Leko, Anand had faced the usual Sveshnikov and played out a draw after failing to force a win with white pieces.
The middle game was fierce with Anand going for the kill right from the early complexities and had Radjabov in trouble.
The game took an exciting course when Anand went for extreme tactics with his 21st move and soon after forced Radjabov to part with his queen.
The youngster, however, got compensation with his passed pawns in the centre and a couple of well-aided pieces. Anand missed an excellent tactical sequence of moves favouring Radjabov and in the end the passed pawns marched ahead in devastating fashion and the game was over in 39 moves.
"He missed a draw and the 33rd move was a blunder," said Radjabov after the game adding that Anand probably missed his Bishop move that held his position together right till the end.
Analysis also showed that Anand might have had Radjabov in big trouble on the 19th turn itself had he opted for a check.
Kramnik played it safe with black and had no trouble whatsoever against Bologan who employed a rather off-beat variation against Sveshnikov.
The middle game here was in contrast to Anand's game with no player really able to make any decisive headway. The outcome was almost clear on the 22nd move itself as the positions repeated twice and just five moves later the draw was agreed.
Leko faced a determined Naiditsch with black and failed to break the fortress of the local hope. The middle game arose from an Anti-Marshall system with equal chances for both and Naiditsch curbed Leko's assault on the king side with timely exchange of queens.
The German was saddled with a bad dark coloured bishop thereafter but in the end it helped a great deal in defending his pawns. After the 45th move, Leko decided it was futile to try for a victory.
Results round 2:
V Anand (0.5) lost to Teimour Radjabov (1, Aze); Viktor Nologan (1.5, Mda) drew Vladimir Kramnik (1.5, Rus); Peter Leko (1, Hun) drew Arkadi Naiditsch (0.5, Ger).
The moves:
V Anand - Teimour Radjabov
1. e4 c5 2. Nf3 Nc6 3. d4 cxd4 4. Nxd4 e5 5. Nb5 d6 6. c4 Be7 7. b3 f5 8. exf5 Bxf5 9. Bd3 e4 10. Be2 a6 11. N5c3 Bf6 12. O-O Nge7 13. a3 O-O 14. Ra2 Qa5 15. b4 Qe5 16. Re1 b5 17. cxb5 axb5 18. Bxb5 Nd4 19. Bf1 d5 20. Rd2 Be6 21. f4 Qxf4 22. Rf2 Qxf2+ 23. Kxf2 Nb5 24. Kg1 Nxc3 25. Nxc3 Bxc3 26. Bb5 Bxe1 27. Qxe1 Nf5 28. Bb2 Rac8 29. Ba4 Rf7 30. h3 h5 31. b5 h4 32. Be5 d4 33. b6 e3 34. Kh2 d3 35. Qb4 e2 36. Bc3 Rxc3 37. Qxc3 Ng3 38. b7 Rxb7 39. Qa5 Rb8 white resigned.
Peter Leko - Arkadi Naiditsch
1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O Be7 6. Re1 b5 7. Bb3 O-O 8. a4 b4 9. d3 d6 10. a5 Be6 11. Nbd2 Bxb3 12. Nxb3 Re8 13. Bg5 h6 14. Bh4 d5 15. Nfd2 d4 16. Nc4 Nd7 17. Bg3 Rb8 18. Rf1 Rb5 19. Qg4 g5 20. h4 Nf6 21. Qf5 Qd7 22. Qxd7 Nxd7 23. hxg5 hxg5 24. f3 Nf8 25. Be1 Ne6 26. Bd2 Kg7 27. Nc1 Rh8 28. b3 Rbb8 29. Ne2 Rh7 30. Ng3 Bc5 31. Kf2 Rbh8 32. Rh1 Rxh1 33. Nxh1 f6 34. g3 Ned8 35. Kg2 Nf7 36. f4 gxf4 37. gxf4 Nd6 38. Nxd6 cxd6 39. Ng3 Kf7 40. Nf5 Ke6 41. Ng7+ Kf7 42. Nf5 Rh7 43. Kg3 Ke6 44. Nh6 exf4+ 45. Bxf4 draw agreed.
Viktor Bologan - 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. Re1 Bg7 15. c3 O-O 16. Qh5 e4 17. Bf1 Re8 18. Rad1 Qc8 19. Nc2 Ng6 20. Nb4 Ne5 21. Nc2 Ng6 22. Nb4 Ne5 23. h3 Rb8 24. Nc2 Ng6 25. Nb4 Ne5 26. Nc2 Ng6 27. Nb4 draw agreed.