Novak Djokovic pulls out injured against Stan Wawrinka: “You feel like you're not able to hit the shot any more"

Novak Djokovic is out of the US Open after quitting, because of injury. The defending champion, 32, retired with a shoulder problem seconds after a double fault left him two sets and a break down against Swiss 23rd seed Stan Wawrinka in the fourth round. "I'm sorry for the crowd. They came to see a full match but it wasn't to be," said world number one Djokovic. “It is very frustrating. Of course, it hurts that I had to retire. Some days the pain has been higher, some days with less intensity. Obviously I was taking different stuff to kill the pain instantly. Sometimes it works, sometimes it doesn't. You just know when you know, when you feel like you're not able to hit the shot any more."

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