Cilic of Croatia flattens the ball with his racquet as he returns to Federer of Switzerland during their...
Marin Cilic of Croatia flattens the ball with his racquet as he returns to Roger Federer of Switzerland during their semi-final match at the 2014 U.S. Open tennis tournament in New York, September 6, 2014. REUTERS/Mike Segar (UNITED STATES - Tags: SPORT TENNIS TPX IMAGES OF THE DAY)