World champion Viswanathan Anand [Images] suffered a shocked defeat against Norwegian prodigy Magnus Carlsen [Images] in the sixth round to slump to joint fourth of Magistral Ciudad de Linares chess tournament in Linares on Thursday.

With his second loss in the first six rounds, Anand has now three points out of a possible six and will have to do a lot of catching up in the remaining eight rounds of the Super Grandmasters tournament.

Anand now shares joint fourth spot with Vassily Ivanchuk of Ukraine while Alexander Grischuk of Russia [Images] shot into sole lead on 4.5 points after shocking Levon Aronian of Armenia in another sensational result.

Aronian and Carlsen share the second spot on 3.5 points each while Lenier Dominguez of Cuba stands sole sixth on 2.5 points, a half point clear of Wang Yue of China and Teimour Radjabov of Azerbaijan.

Carlsen has been tipped by many experts as the future world champion not without reasons. The Norwegian showed immaculate technique to beat Anand for the first time ever in a Classical game.

Anand, who rallied from a hopeless position to draw against Ivanchuk in the previous round, had also lost to Aronian in the second round.

Clearly the world champion was not at his best form and Carlsen took full advantage of that in the game which lasted 77 moves.

It was a Semi Slav defense wherein Carlsen went for a topical variation and Anand employing new idea to trade queens at the cost of a weakened pawn structure. White had a small but lasting advantage when the dust subsided and Carlsen went for a long grind that left the followers of the game baffled.

Exchange of pieces at regular intervals led to a rook and minor piece endgame wherein Carlsen knocked down one pawn to increase his advantage after Anand missed his last chance of survival on the 57th move.

Grischuk was playing the tournament of his life if his results are any indication. The Russian was at his savagely best in crushing Aronian in another Semi Slav of the day.

Playing white, Grischuk went for the Moscow [Images] variation and did not have much trouble in attaining an advantageous middle game. He increased his pressure on the king side and landed the decisive blow on the 41st move to win a rook for knight. Aronian called it a day after 59 moves.

Ivanchuk failed to judge his position to perfection in a drawn affair against Dominguez. After a well played middle game, the Ukrainian had a clear better position on board when he suddenly decided to agree to a draw.

In other game of the day, Wang Yue and Radjabov fought hard in a king's Indian defense with the former playing with black pieces. Radjabov's experience in the opening came in handy as he exchanged pieces at regular intervals to reach a level knight and pawns endgame. The draw was agreed to after 41 moves.

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