In the US Open Tennis, Indo Czech duo of Leander Paes and Radek Stepanek stormed into the doubles semifinals. They beat Julian Knowle of Austria and Filip Polasek of Slovakia 6-2, 6-4 in the quarterfinals on the Flushing Meadows hardcourts in NewYork.In the Men's Singles Quarterfinal, Andy Murray of Britain beat Marin Cilic of Croatia 3-6, 7-6, 6-2, 6-0, while Juan Martin Del Potro of Argentina beat Andy Roddick of US 6-7, 7-6, 6-2, 6-4. In another quarterfinals, Novak Djokovic of Serbia beat 18-Stanislas Wawrinka of Switzerland 6-4, 6-1, 3-1, while Janko Tipsarevic of Serbia beat Philipp Kohlschreiber of Germany 6-3, 7-6, 6-2.In Women's Singles Quarterfinal matches on Serena Williams of US beat Ana Ivanovic of Serbia 6-1, 6-3, while Maria Sharapova of Russia beat Marion Bartoli of France 3-6, 6-3, 6-4. Sara Errani of Italy beat 20-Roberta Vinci of Italy 6-2, 6-4 in another match.