A draw would have sufficed but Grandmaster Koneru Humpy showed no mercy and recorded her second successive win against Shen Yang of China to storm into the semifinals of the World Women's Chess Championship in Nalchik (Russia [Images]).

In the second quarterfinal match, Humpy displayed top form yet again and Yang, once again, proved no match for the vastly superior Indian.

In the first game of the quarterfinals too, Humpy had comprehensively beaten Yang and her second straight victory over the Chinese will also help the Indian add some valuable Elo points in her present rating.

In the semifinals, Humpy will be up against another Chinese player, Yifan Hao, who eliminated Lilit Mkrtchian of Armenia in the quarterfinals. 

In the other quarterfinals matches, Pia Cramling of Sweden played out a draw with Antoatneta Stefanova of Bulgaria to win by 1.5-0.5 margin while Alexandra Kosteniuk of Russia outplayed Anna Ushenina of Ukraine to qualify for the semifinals.

Humpy played the Nimzo Indian defence with her black pieces in the return game and equalised fairly easily early in the middle game. Yang was obviously under pressure to level the scores but her plan to pursue for a victory was not adequate.

Humpy got advantage after Yang went for unwarranted complications and seized the initiative decisively once her queen got to the seventh rank. Yang lost two rooks for two minor pieces in trying to find some defensive resources and it was all over in 42 moves.

Kosteniuk scored a fluent victory over Anna Ushenina in another Nimzo Indian of the day where black excelled. It was a complicated middle game wherein the Ukrainian erred and was saddled with an uncastled king in an open position. A master of attack, Kosteniuk did not give many chances and cruised home in just 25 moves.

Yifan Hao also displayed her tactical acumen against Mkrtchian. A seemingly quite treatment to the Caro Kann as white led to wild complexities in the middle game after Yifan launched an attack and later sacrificed two pieces for a rook to turn the tide in her favour.

Mkrtchian lasted 38 moves before calling it a day.

Stefanova was shown the exit door by Cramling after a tense game arising out of a queen pawn opening where the former played black. Stefanova won a pawn but left her rook hanging via a tactical sortie.

After winning the exchange Cramling just continued nonchalantly and the game was drawn after 49 moves.

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