Top-seeded Novak Djokovic advanced to the quarterfinals of the China Open after American Mardy Fish withdrew with a left ankle injury. Top-seeded Caroline Wozniacki defeated Sara Errani 6-4, 6-2, while Francesca Schiavone rallied for a 4-6, 6-3, 6-1 victory over Vera Dushevina. Nikolay Davydenko edged Marin Cilic 7-5, 7-5. He'll face American John Isner, who beat Philipp Kohlschreiber 7-6 (3), 3-6, 6-3 in a match that featured a combined 33 aces. Read more: http://sports.espn.go.com/sports/tennis/news/story?id=5654106
