PERTH, AUSTRALIA - JANUARY 01: John Isner of the USA serves to Jo Wilfried Tsonga of France in his singles match during day four of the Hopman Cup at Perth Arena on January 1, 2013 in Perth, ... more 

PERTH, AUSTRALIA - JANUARY 01: John Isner of the USA serves to Jo Wilfried Tsonga of France in his singles match during day four of the Hopman Cup at Perth Arena on January 1, 2013 in Perth, Australia. (Photo by Paul Kane/Getty Images) less