World number one Novak Djokovic has been forced to pull out of the Paris Masters due to a recurring shoulder injury.
The 24-year-old was passed fit yesterday and defeated Viktor Troicki to reach the quarter-finals.
Despite playing through the injury, which he picked up in the semi-final clash in Basel last week, the Serbian has decided to drop out of the tournament in France.
"I have pushed myself to the limit by playing, and after the match yesterday my shoulder got worse," Djokovic posted on Twitter.
"For this reason, i have to put my health first and withdraw even though my urges as a professional player are making me want to play until the last drop of energy. I am very sorry for all of you who bought tickets and wanted to come to watch me play.
"My season has been long and tiring, i played all of my matches at my highest level, and now my body is aching for recovery. Hoping for your understanding and support."
The US Open champion will now miss out on claiming a £1m cash bonus, but he is due to compete in the World Tour Finals in London later this month.
Frenchman Jo Wilfried-Tsonga, who was due to face Djokovic in the quarter-finals this afternoon, is now automatically in the semi-finals and will face either David Ferrer or John Isner.