Viswanathan Anand committed an uncharacteristic blunder and lost to Hikaru Nakamura of USA in the fourth round of the London Chess Classic 2011.
This incidentally is the first time that Nakamura has scored over the world champion and this victory came with the Black pieces.
The high voltage game of the round between Magnus Carlsen of Norway and Vladimir Kramnik of Russia ended with honours shared.
Luke McShane continued to show good form and defeated his English compatriot David Howell while Nigel Short opened his account with a victory over out of form Michael Adams.
The Category 20 event, played under Classical time control, has nine players and has three points at stake for a victory while a draw allows just one point Carlsen and McShane now have emerged joint leaders with eight points each while Nakamura follows them with seven points.
Kramnik is next with five points followed by Aronian with three. Short is next with three points while Anand, Howell and Adams are bunched at the bottom with two points each.
Anand once again stuck to the Queen Pawn opening and Nakamura responded with the sharp King’s Indian Attack.
However, the Indian GM was on top in the opening and Nakamura appeared to be in deep trouble.
A wrong knight move on the 29th turn proved disastrous for Anand as suddenly he was starting at a serious loss.
