Davis Cup: Roger Federer ‘hopeful’ over Davis Cup final | CNN

The elite eight at the World Tour Finals —

Roger Federer, left, and Novak Djokovic, right, headlined the World Tour Finals in London, but the Swiss star had to pull out of the final due to a back injury. The year-end championships featured eight of the world's best tennis players.

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The elite eight at the World Tour Finals —

Djokovic's finest moment this year came when he won a second Wimbledon title by defeating Federer in an absorbing five-set match. He's the two-time defending champion at the World Tour Finals.

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The elite eight at the World Tour Finals —

Federer is making his 13th consecutive appearance at the event. He rebounded this season after a bad back hindered his 2013.

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The elite eight at the World Tour Finals —

But will Federer be fully focused in London? He'll lead Switzerland in the Davis Cup final in late November. The Davis Cup is one of the few prizes in tennis Federer hasn't won.

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The elite eight at the World Tour Finals —

Federer's countryman, Stan Wawrinka, earned his London spot thanks largely to winning the Australian Open in January. But he's slumping entering the year-end championships.

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The elite eight at the World Tour Finals —

Exciting Japanese baseliner Kei Nishikori became the first Asian man to contest a grand slam singles final when he reached the last stage of the U.S. Open. He has defeated both Djokovic and Federer in 2014.

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The elite eight at the World Tour Finals —

Andy Murray desperately wanted to play at the year-end championships, competing for six straight weeks down the stretch. In the end he qualified -- and comfortably. Recovering from back surgery and splitting with coach Ivan Lendl made the first part of the year difficult for the Scot and 2013 Wimbledon champion.

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The elite eight at the World Tour Finals —

Tomas Berdych is becoming a regular at the World Tour Finals. The always dangerous Czech reached the quarterfinals or better at three majors this year -- although given his weapons some would say he could do even better.

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The elite eight at the World Tour Finals —

At the age of 23, Milos Raonic is already Canada's best ever men's singles player. Raonic made the semifinals at Wimbledon and last week beat Federer -- who downed him at the All England Club -- for the first time.

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The elite eight at the World Tour Finals —

The third of three debutants in London, joining Nishikori and Raonic, Croatia's Marin Cilic didn't drop a set against Berdych, Federer and Nishikori as he won the U.S. Open in September. A year ago he served a drug suspension, which was subsequently shortened on appeal.

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The Super Eight

Story highlights

Roger Federer faces fitness battle to be ready for Davis Cup final

Said he wasn't "match fit" for final of World Tour finals against Novak Djokovic

Federer had played for about three hours Saturday in beating fellow Swiss Stan Wawrinka

Davis Cup final between Switzerland and France starts Friday in Lille

CNN —

Swiss star Roger Federer faces a race against time to be fit for the Davis Cup final against France.

The 33-year-old Federer pulled out of the final of World Tour Finals against Novak Djokovic Sunday due to a back injury, raising doubts over his participation in the showpiece match that starts in Lille on Friday.

“We will have to see how severe those back problems are and we hope that Roger will be able to recover until next Friday,” the Swiss Davis Cup captain Severin Luthi said in a statement on Facebook, referring to the final that is being staged November 21-23.

“He now has to rest,” added Luthi. “Our team doctor Roland Biedert has come to London and, together with our physiotherapist Daniel Troxler, will work on Roger’s fast recovery.”

But speaking at a news conference on Tuesday, Federer sounded cautiously optimistic.

“My back is better than it was Sunday, but not good enough for practice yet. But I’m hopeful,” he said.

After pulling out of Sunday’s final against Djokovic, Federer adopted a more optimistic tone than Luthi.

“This back spasm [or] whatever it might be, it’s just not a fun thing to have during the day,” Federer said on the official Davis Cup website.

“It’s just uncomfortable. But I’m positive and I’m hopeful that it’s going to go away very soon.”

Federer was plagued by back issues in 2013, largely contributing to a subpar campaign – by his illustrious standards.

He has enjoyed good health in 2014, though, one of the reasons the 17-time grand slam champion was able to No. 2 in the world rankings.

The Swiss star picked up the injury in the third-set tiebreaker of his late-night 4-6 7-5 7-6 (6) victory over Davis Cup teammate Stan Wawrinka Saturday.

Wawrinka crunched a backhand at Federer when the latter was at the net and also, at one stage, Wawrinka jawed at the Federer camp, seemingly unhappy with something that was said to him.

The Davis Cup title, along with an Olympic singles gold medal, is one of the few gaps in Federer’s resume.

Read: Djokovic wins World Tour Finals after Federer pulls out

Read: Federer saves sets points