(FILE PHOTO) Rafael Nadal,Grand Slam champion, will retire from tennis at the end of this season. PARIS, FRANCE - JUNE 03: Rafael Nadal of Spain waves to the fans after defeat in his Men's quarter final match against Novak Djokovic of Serbia on day eleven of the 2015 French Open at Roland Garros on June 3, 2015 in Paris, France. (Photo by Clive Brunskill/Getty Images)