Ivo Karlovic, of Croatia, returns the ball to Roger Federer, of Switzerland, during a match at the Sony Open tennis tournament, Friday, March 21, 2014, in Key Biscayne, Fla. (AP Photo/Lynne Sladky)
Roger Federer, of Switzerland, leaps into the air after defeating Ivo Karlovic, of Croatia, 6-4, 7-6 (7-4) at the Sony Open tennis tournament, Friday, March 21, 2014, in Key Biscayne, Fla. (AP Photo/Lynne Sladky)