World No. 1 Novak Djokovic was forced to call off his US Open title defence, retiring from his fourth-round match against Swiss 23rd seed Stan Wawrinka due to a left shoulder injury on Sunday evening on Arthur Ashe Stadium.
The Serb cited a shoulder injury that has been lingering on and off for the last couple of weeks and first caused him considerable pain during the second round of the US Open against Argentine Juan Ignacio Londero.
2016 Flushing Meadows champion, Stan Wawrinka led Djokovic 6-4, 7-5, 2-1 when the 16-time Grand Slam champion quit, having received treatment on his troublesome left shoulder after the second set.
The 32-year-old was the hot favourite to retain his title in New York and win a 17th Grand Slam crown.
Top-ranked Novak Djokovic was also attempting to become the first man to defend the US Open since Roger Federer in 2008.
The Serbian will now focus on fixing his shoulder and plans to be back in four weeks at the Rakuten Japan Open Tennis Championships before defending his title at the Rolex Shanghai Masters.
Djokovic has held the No. 1 spot in the ATP rankings for over 260 weeks and is currently looking to tie Pete Sampras’ record of six year-end No. 1 finishes.
Djokovic declared in his post-match press conference that:
“It was the left shoulder, unfortunately, it is frustrating. Very frustrating. Obviously not the first, not the last player to get injured and to withdraw from one of the biggest events in sport. But obviously I just came off the court, so of course it hurts.”
“Evaluation is to come. I did a lot of treatment and diagnostics in the last couple of weeks, but I have to do it again. I hope that I’ll be able to play Tokyo.”
Former World No. 3 Stan Wawrinka has won three Grand Slam singles titles, beating the No. 1 player in the world at the time in all three finals. He won the 2014 Australian Open - defeating Rafael Nadal in four sets, the 2015 French Open - crushing Djokovic in four sets and the 2016 US Open - shocking the current World No. 1 in four sets.
Stan Wawrinka has advanced to the quarter-finals in Flushing Meadows and will next face Cincinnati champion Daniil Medvedev for a place in the semi finals.
"It's never the way you want to finish a match. I'm sorry for Novak. He's an amazing champion." The Swiss said.