Viswanathan Anand [Images] allowed a great winning opportunity to slip by and had to be content with a draw in the fourth round against Alexander Morozevich in the World Chess Championships in Mexico.

Anand, with a draw in 57 moves stays in shared lead with Vladimir Kramnik, both having 2.5 points from four games. Four players, including Moro, Alexander Grischuk, Boris Gelfand and Lev Aronian have two points each. Peter Leko and Peter Svidler have 1.5 points each.

For the third day in a row Anand was in a featured game - this one against Morozevich, considered to be one of the most original top class players. Moro had just recovered from the second round loss to Kramnik and the outplayed Svidler in third.

The Moro-Anand game went into the fashionable Meran variation of the Slav defence. The duo played at a blitz-like speed along well known lines.

Once again from here Anand showing great preparations came up with completely different new plan and Morozevich has to find how to react, as such positions can easily turn in Black's favor.

After a strong opening, Anand had a variety of options in middle game and consolidated some advantage. White was forced to win an exchange but a black pawn got to d3 and was supported by a powerful pair of bishops.

As the players began to play faster, Anand had decisive advantage but the question was whether he really needed to go for the knight sacrifice earlier. Yet at this stage after 40 moves, Anand's win looked only a matter of time.

Anand wanting to finish the game fast seemed to be going strong. Morozevich's king was in delicate situation and though the material was equal, it was hard to find adequate moves.

Anand after Moro's 56. Be6 looked very close to a win. But he slipped there and according to analysts allowed Moro back into the game at that stage. A few moves later Moro had warded off the threat and a draw was agreed after 61 moves.

Anand must have been disappointed as he had the advantage throughout the game till he missed a chance towards the end in a completely winning position. Morozevich was stubbornly finding defensive resources and was rewarded by achieving to draw in this seemingly hopeless game.

Kramnik was held to a draw by Grischuk in 60 moves from a Catalan. Grischuk fought well and held out for a good draw.

Aronian handed Leko a solid defeat in 45 moves from English Symmetrical start and Svidler and Gelfand were engaged in a short 24-move draw from Petroff.

Pairings for Round 5: (on September 18); Anand Svidler; Gelfand v Aronian; Grischuk v Morozevich; Leko v Kramnik

Results of Round 4: Kramnik draw with Grischuk; Aronian beat Leko; Morozevich drew with Anand; Svidler drew with Gelfand

Standings after Round 4: 1. Anand and Kramnik 2.5; 3. Grischuk, Gelfand, Morozevich and Aronian 2.0; 7. Svidler and Leko 1.5;

Morozevich v Anand
Round 4, World Chess Championships, Mexico 2007

1.d4 Nf6 2. c4 e6 3. Nf3 d5 4. Nc3 c6 5. e3 Nbd7 6. Bd3 dxc4 7. Bxc4 b5 8. Bd3 Bb7 9. O-O a6 10. e4 c5 11. d5 c4 12. Bc2 Qc7 13. dxe6 fxe6 14. Nd4 Nc5 15. Be3 e5 16. Nf5 g6 17. Nh6 Bg7 18. Qf3 Ne6 19. Qh3 Bc8 20. Qh4 Qe7 21. Rfe1 Nd5 22. Qxe7+ Nxe7 23. Nd5 Bb7 24. Ng4 Nd4 25. Bd1 Nxd5 26. exd5 O-O-O 27. Bg5 Rxd5 28. b3 c3 29. Ne3 Rc5 30. Rc1 Rc7 31. b4 Kb8 32. h3 h6 33. Bh4 Nf5 34. Nxf5 gxf5 35. Bc2 Rc4 36. Be7 e4 37. Bb3 Rd4 38. Bc5 Rd3 39. Be6 Bc8 40. Bb3 Re8 41. Bf7 Re5 42. Be3 Re7 43. Bg6 Be6 44. h4 Bxa2 45. Bxf5 Bd5 46. Bc5 Re8 47. f3 Kb7 48. fxe4 Bc6 49. Kf2 Rd2+ 50. Ke3 Be5 51. Kf3 Red8 52. Re3 Rg8 53. g4 Rh2 54. h5 Rd8 55. g5 Rxh5 56. Be7 Re8 57. Kg4 Rh2 58. Bf6 Rg2+ 59. Kh3 Rh2+ 60. Kg4 Rg2+ 61. Kh3 1/2-1/2

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