World number four Novak Djokovic is doubtful for the US Open--the upcoming fourth and final major of the season--due to an elbow injury.
According to a Serbian newspaper, Serbia's doctor Zdenko Milinkovic said Djokovic would require a rest for six to 12 weeks, which will most likely rule him out of the rest of the ATP Tour season.
"Symptoms have calmed down. He was with a specialist in Toronto for additional tests. He also consulted our experts. Now it's important to look at the different types of procedures that can affect recovery," the Sydney Morning Herald quoted Milinkovic as saying.
The former world number one, who has been struggling with form this season, suffered a fresh blow earlier this month when an elbow injury curtailed his chance to lift the Wimbledon title for the fourth time.
Djokovic came into the match with a 25-2 head-to-head record against Tomas Berdych, but retired while trailing 7-6(2), 2-0.
The Serbian maestro has endured a turbulent 12 months after becoming the first man since Rod Laver in 1969 to hold all four grand slams at the same time following his French title last year.
He has failed to add another major title to his account, bowing out of the Australian Open in the second round before making a quarter-final exit at the French Open.