Novak Djokovic of Serbia in action against Tomas Berdych of the Czech Republic during their men’s single quarter final match at the French Open tennis tournament at Roland Garros in Paris, France, 02 June 2016. EPA/STEPHAN MUELLER

Novak Djokovic of Serbia in action against Tomas Berdych of the Czech Republic during their men’s single quarter final match at the French Open tennis tournament at Roland Garros in Paris, France, 02 June 2016. EPA/ROBERT GHEMENT

Novak Djokovic of Serbia in action against Tomas Berdych of the Czech Republic during their men’s single quarter final match at the French Open tennis tournament at Roland Garros in Paris, France, 02 June 2016. EPA/ROBERT GHEMENT

Novak Djokovic of Serbia in action against Aljaz Bedene of Britain during their men’s single third round match at the French Open tennis tournament at Roland Garros in Paris, France, 28 May 2016. EPA/ROBERT GHEMENT

Novak Djokovic of Serbia in action against Roberto Bautista Agut of Spain during their men’s single round of 16 match at the French Open tennis tournament at Roland Garros in Paris, France, 01 June 2016. EPA/IAN LANGSDON

Novak Djokovic of Serbia in action against Aljaz Bedene of Britain during their men’s single third round match at the French Open tennis tournament at Roland Garros in Paris, France, 28 May 2016. EPA/STEPHAN MUELLER