2015 French Open - Day Six [Getty Images]

PARIS, FRANCE - MAY 29: Stanislas Wawrinka of Switzerland returns a shot in his Men's Singles match against Steve Johnson of the United States on day six of the 2015 French Open at Roland Garros on May 29, 2015 in Paris, France. (Photo by Clive Mason/Getty Images)

Getty Images Sport Clive Mason