By Richard Pagliaro | Friday, August 4, 2017

Stan Wawrinka closed the curtain on his season to recover from a chronic knee injury.

The fourth-ranked Swiss announced he has ended his season to “undergo a medical intervention” on his knee.

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Wawrinka, who has not won a match since reaching the Roland Garros final, announced his decision on Facebook.

“After sitting together with my team and considering all options, I have made the very difficult decision to end my 2017 season as I need to undergo medical intervention on my knee," Wawrinka said. "This is obviously extremely disappointing, but I’m already looking ahead and planning my recovery.

"I love this sport and I will work hard to get back to my top level and play for many more years. I also want to take this opportunity to thank my fans who have sent plenty of messages of support during the past few days."



The reigning US Open champion’s departure means the Flushing Meadows major will be without both its 2016 champion and runner-up, Novak Djokovic, who pulled the plug on his season on July 26th to rehab a nagging elbow injury.

The 32-year-old Wawrinka becomes the third reigning champion in recent years unable to defend the US Open because of injury.

Juan Martin del Potro, the 2009 US Open champion, was sidelined in 2010 with a wrist injury.

Rafael Nadal won his second US Open title in 2013 and could not defend in 2014 due to injury.

Following his first-round Wimbledon loss to 49th-ranked Daniil Medvedev, Wawrinka said he’s been bothered by the knee issue since late last year.

“It's not something new, but something I had in the past,” Warinka said at Wimbledon. “End of last year and also in Australia.

“But, again, since I had that problem, was the first time I'm playing on grass. Apparently grass is not the best surface for my knee. I need to figure it out exactly what's the problem now, what I'm going to do, and come back on the tennis court when I will feeling without any pain.”

Since the 2015 Roland Garros champion lost to Rafael Nadal in the French Open final, he's played just two matches losing his Queen's Club opener to Feliciano Lopez before his first-round exit from Wimbledon.

The three-time Grand Slam champion concludes 2017 with a 26-11 record, including winning his 16th career title in Geneva.