Roger Federer of Switzerland returns to Milos Raonic of Canada during their semi-final match of the Wimbledon Championships at the All England Lawn Tennis Club, in London, Britain, 04 July 2014. EPA/FACUNDO ARRIZABALAGA

Roger Federer of Switzerland returns to Milos Raonic of Canada during their semi-final match of the Wimbledon Championships at the All England Lawn Tennis Club, in London, Britain, 04 July 2014. EPA/ANDY RAIN

Roger Federer of Switzerland celebrates a point against Milos Raonic of Canada during their semi-final match of the Wimbledon Championships at the All England Lawn Tennis Club, in London, Britain, 04 July 2014. EPA/ANDY RAIN

Milos Raonic of Canada returns to Roger Federer of Switzerland during their semi-final match of the Wimbledon Championships at the All England Lawn Tennis Club, in London, Britain, 04 July 2014. EPA/FACUNDO ARRIZABALAGA

Grigor Dimitrov of Bulgaria returns to Novak Djokovic of Serbia during their semi-final match of the Wimbledon Championships at the All England Lawn Tennis Club, in London, Britain, 04 July 2014. EPA/ANDY RAIN