Florian Mayer has pulled out of the U.S. Open. The 62nd-ranked German hasn't played since March, when he withdrew from his match against Novak Djokovic at Key Biscayne because of a groin injury. He missed the French Open and Wimbledon. His withdrawal from the U.S. Open was announced Thursday. See more at http://espn.go.com/tennis/usopen14/story/_/id/11260145/florian-mayer-germany-pulls-us-open