Grandmaster Koneru Humpy suffered a shock defeat at the hands of Chinese teenager Yifan Hao in the first game of the semi-finals of the Women's World Chess championship on Wednesday.

The Indian, who started as the highest rated player in the knock-out championship, will now have to win the return game on Thursday to remain in contention.

As the rules are if the results are tied after two games, tiebreak games of shorter duration are played to determine the winner.

Playing in third world championship, Humpy will be under pressure in the return game having lost in the semis of the 2004 World championship as well when lower ranked Ekaterina Kovalevskaya of Russia [Images] had beaten her.

Making matters worse for Humpy is the fact that she was comprehensively outplayed.

14-year old Yifan Hao has been going under intense chess training for many years and today was just another indication of her growing chess sense. Playing white in the Ruy Lopez Brayer, the teenager showed class and temperament to handle top class opposition.

The middle game saw Yifan emerging slightly better and then on the 20th move a pawn advance ensured a tangible advantage for her.

Humpy took the temporary pawn sacrifice but her position worsened after a few swaps on the queen side. Gaining more control, Yifan successfully exchanged the queens and knocked down one pawn on the 31st move.

It was a hopeless situation thereafter for Humpy who later lost a piece and eventually resigned. In the other semi-final, Alexandra Kosteniuk of Russia defeated Pia Cramling of Sweden.

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