Sabine Lisicki of Germany in action against Monica Puig of Puerto Rico during their first round match for the French Open tennis tournament at Roland Garros in Paris, France, 25 May 2015. EPA/ETIENNE LAURENT

Roberta Vinci of Italy in action against Alize Cornet of France during their first round match for the French Open tennis tournament at Roland Garros in Paris, France, 25 May 2015. EPA/ROBERT GHEMENT

Andy Murray of Britain in action against Facundo Arguello of Argentina during their first round match for the French Open tennis tournament at Roland Garros in Paris, France, 25 May 2015. EPA/ROBERT GHEMENT

Venus Williams of the USA in action against Sloane Stephens of the USA during their first round match for the French Open tennis tournament at Roland Garros in Paris, France, 25 May 2015. EPA/ETIENNE LAURENT

Maria Sharapova of Russia in action against Kaia Kanepi of Estonia during their first round match for the French Open tennis tournament at Roland Garros in Paris, France, 25 May 2015. EPA/ROBERT GHEMENT