India's tennis star Sania Mirza remained on course for her second successive Grand Slam title after reaching the semifinals of the US Open with Swiss partner Martina Hingis, in New York. In semifinals they will face 11th seed Italians Sara Errani and Flavia Pennetta this evening.In the quarterfinals, top seeds Sania and Hingis, the Wimbledon champions, saw off the challenge of Taipei girls Yung-Jan Chan and Hao-Ching Chan 7-6(5) 6-1. In the men's doubles quarter-finals Rohan Bopanna and Florin Mergea will take on Dominic Inglot and Robert Lindstedt in the quarterfinals.Bopanna is also in contention in the mixed doubles event where he and his partner Yung-Jan Chan are up against Leander Paes and Martina Hingis in the semifinals.