Rafael Nadal of Spain reacts during a men’s second round singles match against Peter Gojowczyk of Germany in the China Open tennis tournament at the National Tennis Center in Beijing, China 02 October 2014. EPA/ROLEX DELA PENA

Rafael Nadal in action against Fernando Verdasco in a new fast format of tennis called Fast 4 at the Margaret Court Arena in Melbourne, Australia, 14 January 2015. The Australian Open begins on Monday. EPA/DAVID CROSLING AUSTRALIA AND NEW ZEALAND OUT

Rafael Nadal of Spain in action during his men’s final match against Stanislas Wawrinka of Switzerland, at the Australian Open Grand Slam tennis tournament in Melbourne, Australia, 26 January 2014. EPA/MARK DADSWELL AUSTRALIA AND NEW ZEALAND OUT

Rafael Nadal of Spain reacts after defeating Philipp Kohlschreiber of Germany during their match on the eighth day of the 2013 US Open Tennis Championship at the USTA National Tennis Center in Flushing Meadows, New York, USA, 02 September 2013. The US Open runs through Monday 09 September, a 15-day schedule for the first time. EPA/JASON SZENES

Rafael Nadal, of Spain, returns a volley to Roger Federer, of Switzerland, during the quarter-final round of the ATP Masters in Mason, Ohio, USA, on 16 August 2013. Nadal won 7-5, 4-6, 6-3. EPA/MARK LYONS