see more

MELBOURNE, AUSTRALIA - JANUARY 28: Stanislas Wawrinka of Switzerland and Kei Nishikori of Japan at the net after Wawrinka won their quarterfinal match during day 10 of the 2015 Australian Open at Melbourne Park on January 28, 2015 in Melbourne, Australia. (Photo by Cameron Spencer/Getty Images)

MELBOURNE, AUSTRALIA - JANUARY 28: Stanislas Wawrinka of Switzerland and Kei Nishikori of Japan at the net after Wawrinka won their quarterfinal match during day 10 of the 2015 Australian Open at Melbourne Park on January 28, 2015 in Melbourne, Australia.  (Photo by Cameron Spencer/Getty Images)