Roger Federer said he believes that his rival Rafael Nadal will be a perennial title contender again when he regains his old form in 2015 after being slowed down by injuries this year.

Nadal missed the 2014 ATP World Tour Final for the second time in three years after suffering from appendicitis just weeks after returning from a long layoff because of a wrist injury.

The Spanish tennis superstar, who also failed to defend his title at the 2014 U.S. Open because of his ailing wrist, also missed the ATP year-end tournament in 2012 because of a knee injury.

Rafael Nadal

Nadal said in an interview with USA Today that he expects Nadal to be “back to normal” next year, adding that the 14-time Grand Slam champion will always be in contention for major titles again.”I think he’ll be playing for the biggest titles in the sport and maintaining his ranking and moving up again,” Federer said. “I think that’s what he expects from himself and that’s what I hope we’ll see again.”

Federer has had numerous epic battles with Nadal since 2004 but has only played against each other once this year because the Mallorca, Spain, native has been battling numerous injuries since the start of the year.

Aside from the wrist injury and appendicitis, Nadal was also bothered by an ailing back earlier in the season, which affected him during his final showdown against Stanislas Wawrinka at the 2014 Australian Open. Recent reports indicated that Nadal is planning to undergo stem cell treatment on his back.

Wawrinka, Federer’s compatriot, is also hoping that Nadal will regain his old form next year. And if Nadal stays healthy, Wawrinka said that the former World No. 1 will continue to a big threat in every tournament.

“For me, if Rafa is fit again without injuries, he’s going to be back at the top again for sure,” Wawrinka said. “Every time he comes back he almost wins everything. We’ll see. I hope he’s going to be fit again and not injured, but it’s going to be interesting for [2015].”