Grandmaster Koneru Humpy could not breach Betul Cemre Yildiz's defence and settled for a draw against the lowest ranked local favourite in the third round of the IS Bank Attaturk Fide Women's Grand Prix chess tournament now underway in Istanbul.

After two victories against much tougher opponents -- Swede Pia Cramling and Armenian Elina Danielian -- Humpy lost her way against Betul and signed truce to allow the Turkish girl open her account.

In other matches, Second seed Yifan Hao defeated former world champion Antoaneta Stefanova of Bulgaria in a splendid game where the former played black.

After three rounds, Yifan, Martha Baquero Fierro of Ecuador and Zhao Xue of China joined Humpy in lead on 2.5 points out of a possible three.

The four leaders are now a full point clear of Antoaneta, Elina and former world champion Maia Chiburdanidze of Georgia.

It was a game of fluctuating fortunes between Humpy and Betul. Playing the white side of a Sicilian Rossolimo, Betul stood slightly better after the opening but Humpy neutralised the initiative quite easily with timely strikes on the king side.

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