Tommy Haas is not going to win the U.S. Open. At 35, the German is the oldest player in the men’s field and is clearly past his prime. (His peak rank was No. 2 in 2002.) But in 2013, after years beset by injuries, Haas is having a renaissance. He is now ranked No. 13, and he beat Novak Djokovic earlier this year, becoming the oldest man in three decades to defeat a No. 1 player. Clearly Haas is in great physical shape. His mental game, too, is one of the best in the world.