Reigning U.S. Open champion Juan Martin del Potro might defend his title, after all. Despite being sidelined since January because of a right wrist injury that required surgery, del Potro was on the provisional entry list released Thursday by the U.S. Tennis Association for the men's field at the year's last major tournament. The U.S. Open starts Aug. 30. http://sports.espn.go.com/sports/tennis/usopen10/news/story?id=5400795
