Novak Djokovic will sit out the rest of this season because of an injured right elbow, meaning he will miss the US Open and end his streak of participating in 51 consecutive grand slam tournaments.
"It is the most important for me to recover, to be able to play injury free for as long as possible, to compete in the sport that has given me so much, the sport I love," Djokovic said on Wednesday. "Of course I want to return to the winning form, to win again, to win the trophies. But now it is not the time to talk about it. At this point, I'm focusing on recovery."
Until now, Djokovic has never missed a major tournament since he entered his first, the 2005 Australian Open. That is the third-longest active run among men and seventh-longest in history.
In that time, the 30-year-old Serb has won 12 grand slam titles, including the US Open in 2011 and 2015.
"The remarkable series has come to an end," Djokovic said. "My body has its limits, and I have to respect that and be grateful for all that I have achieved so far."
He said that Andre Agassi, who he recently began working with on a part-time basis, will be his coach when Djokovic returns to the tour next year. He plans to start with a tune-up tournament ahead of the Australian Open in January.
"He supports my decision to take a break, and remains my head coach," Djokovic said. "He is going to help me get back into shape and bounce back strong after the recovery period."
Djokovic made his announcement via Facebook, his website and at a news conference in Belgrade, Serbia.
Djokovic's last match was on July 12, when he stopped playing during his Wimbledon quarterfinal against Tomas Berdych because of the elbow. Djokovic said that day he was in pain when he hit serves and forehands.
At the time, Djokovic said he had been struggling with the elbow on his racket-swinging arm for about 1½ years and so far had opted against having surgery - and he reiterated Wednesday that he does not need an operation.
But he also said then that he would seriously consider taking a prolonged break from the tour.
Since winning the 2016 French Open to complete a career Grand Slam and become the first man in nearly a half-century to win four consecutive major trophies, Djokovic's form has dipped. He has fallen from No 1 to No 4 in the ATP rankings and failed to defend any of those titles. He has made it past the quarter-finals at only one of the past five grand slam tournaments: last year's US Open, where he lost in the final to Stan Wawrinka.
Djokovic, who also mentioned on Wednesday that his wife is expecting their second child, reached at least the semifinals at Flushing Meadows each of the past 10 years. That includes seven appearances in the final.
This year's US Open starts on August 28.
Roger Federer demonstrated the benefits of a hiatus from the tour, sitting out the last half of 2016 after Wimbledon to let his surgically repaired left knee to heal fully.
Also read: Graham Caygill writes how Federer renaissance can serve as inspiration to injured Murray and Djokovic
Federer returned at the beginning of this season and won the Australian Open to end a four-and-a-half-year grand slam drought, plus titles at Indian Wells and Miami. He took another break after that, missing the entire European clay-court circuit, and returned for the grass, winning his eighth Wimbledon championship and 19th major title overall - both records for a man - this month.
"All the doctors I've consulted, and all the specialists I have visited, in Serbia and all over the world, have agreed that this injury requires rest. A prolonged break from the sport is inevitable," Djokovic said. "I'll do whatever it takes to recover. I will use the upcoming period to strengthen my body and also to improve certain tennis elements that I have not been able to work on over the past years, due to a demanding schedule."