Barclays ATP World Tour Finals - Day Seven [Getty Images]

LONDON, ENGLAND - NOVEMBER 15: Roger Federer of Switzerland celebrates a point in the singles semi-final match against Stan Wawrinka of Switzerland on day seven of the Barclays ATP World Tour Finals at O2 Arena on November 15, 2014 in London, England. (Photo by Clive Brunskill/Getty Images)

Getty Images Sport Clive Brunskill