Wawrinka back on tennis court from surgery

World No.7 Stan Wawrinka, having recovered from surgery for a recurring knee problem, is back in training before his scheduled comeback in an exhibition event.

World No.7 Stan Wawrinka has returned to training ahead of his scheduled comeback at December's Mubadala World Tennis Championship exhibition event.

Three-time grand-slam winner Wawrinka, 32, last played in July at Wimbledon where he hurt his knee in a shock first-round loss. He withdrew from the US Open and announced the end of his season in August to undergo surgery for a recurring knee problem.

"First practice since July! Sooooo happy and excited!! Already killing the cones with the backhand!" Wawrinka said on his Twitter account along with a video of him back on court.

Serbian Novak Djokovic, who's also on the injury comeback trail, and world No.1 Rafa Nadal are scheduled to play at the Abu Dhabi event, which starts on December 28.