World Champion Viswanathan Anand played out a draw with Vassily Ivanchuk of Ukraine to maintain his sole lead after the end of the Morelia stint of the Morelia-Linares chess tournament here.
The Indian ace played it safe with white after Ivanchuk carried out a fine counter play in the middle game and even though the other three games ended decisively, it did not hamper Anand's status as the sole leader as nearest rival Levon Aronian of Armenia was outdone by Magnus Carlsen of Norway in a classic.
On a day when former World champion Veselin Topalov of Bulgaria made most of the opportunities against a luck-less Peter Leko of Hungary, Latvian-born Spaniard Alexei Shirov also played imaginatively to beat Teimour Radjabov of Azerbaijan.
At the half way stage in the category-21 event among eight players, Anand had 4.5 points to his credit and was followed by Topalov and Shirov a half point behind.
Another half point adrift were Carlsen and Aronian with 3.5 points each while Radjabov and Ivanchuk were now joint fifth on three points apiece. With just 2.5 points in his kitty, Leko was at the bottom of the tables.
The remaining seven rounds of the event will be played at Linares in Spain from February 28.
Anand faced the Sicilian defense from Ivanchuk who opted for a Scheveningen set up. In the middle game, Anand rolled his king side pawns for a probable attack but the Ukrainian kept himself in contention with some timely manoeuvres leading to exchanges.
Anand decided against trying hard once his pawn structure on the queen side was fractured and the game was drawn after the players reached a rook and minor pieces endgame. The game lasted 31 moves.
Magnus Carlsen was in his elements in beating Aronian who played the black side of a Ruy Lopez opening. Carlsen came up with an opening surprise yet again to take Aronian out of routine opening theory and was successful when the Armenian took the bait transposing to a position akin to the Arkhengelsk variation.
Carlsen was on top once Aronian miscalculated and let his Knight travel to the edge of the board in white's territory with little support from other sources and Carlsen used his pieces well to trap the unwanted guest.
Once the knight was captured it was a matter of routine technique for Carlsen.
Topalov defeated Leko in a keenly contested game arising out of a Sicilian Najdorf. Leko erred in the middle game and lost his queen for two rooks at a crucial juncture after which there were little hassles for Topalov. The game lasted just 38 moves.
Shirov showed his penchant for complicated positions and defeated Radjabov with fine display. It was a King's Indian classical where Radjabov did not get his attack rolling on the king side. Shirov won a pawn and never looked back.