By Chris Oddo | Sunday, November 16, 2014

Roger Federer has withdrawn from Sunday afternoon’s ATP World Tour Final in London due to a back issue suffered during yesterday’s three-set semifinal against Stan Wawrinka. Federer came out on court in London to tell the crowd personally that he wasn't fit to compete, and he also took to social media to express his regrets.

“I am sorry to announce that I cannot play the finals tonight vs. Novak,” Federer said on his Facebook page. “I hurt my back late in the match yesterday against Stan. I am very disappointed and I hope to be feeling better soon.”

Federer was bidding for a record seventh ATP World Tour Finals title.

“It’s been an extremely difficult decision because I love playing in London and the ATP World Tour Finals have been an absolute highlight of my career,” he wrote. “Unfortunately, my back problem does not allow me to play right now. I hope all tennis fans and those involved in the event will understand.”

Novak Djokovic wins his fourth title at the event due to Federer’s withdrawal. The Serb, who broke the record for least games lost in round-robin play this week in London, defeated Kei Nishikori in three sets in Saturday’s semifinal round.

"I'm sure that if he could have come out and played he would have," said Djokovic of Federer. "Obviously I feel disappointed for you guys who will not see a match," Djokovic told the crowd. "This was a well-anticipated match between No. 1 and No. 1 of the world and I'm sure everybody was excited to see it."

Djokovic claims the ATP World Finals title for the fourth time, and becomes the first man to win it three times in succession since Ivan Lendl did so in 1987.