Juan Martin del Potro of Argentina holds his racquet up and claps after winning his match against Nicolas Mahut of France during the Sydney International Tennis Tournament in Sydney, Australia, Wednesday, Jan. 8, 2014. (AP Photo/Rob Griffith)
Juan Martin del Potro of Argentina plays a backhand shot in his match against Nicolas Mahut of France during the Sydney International Tennis Tournament in Sydney, Australia, Wednesday, Jan. 8, 2014. (AP Photo/Rob Griffith)