Federer warns Djokovic of repeat performance danger

Roger Federer has warned Novak Djokovic he will find it hard to repeat his incredible 2015 campaign. 

Federer was Djokovic's last victim of the year as the Serb romped to a 6-3, 6-4 victory in the final of the ATP Tour Finals on Sunday. 

It was 28-year-old Djokovic's 11th title of a golden year that saw the world number one win 82 of his 88 matches, reach all four Grand Slam finals and win Wimbledon, the Australian Open and the US Open. 

But 17-time Grand Slam champion Federer knows just how difficult it will be for Djokovic to emulate his triumphs in 2016.

"It's hard to play at this pace all the time. You are talking about narrow margins, a break point here and there can change the whole outcome," Federer said.

"You can't always be on the winning side. Margins are very small at the top. 

"That is why this year of Novak's is amazing. I've been there, Rafa (Nadal) has been there. We both know how hard it is to back it up year after year. 

"It's not the first good year for Novak. Certainly he's going into next year with massive confidence. He's playing great. 

"It's going to be hard for him to have a bad year, but you can't just repeat a year like this. 

"It takes a lot of effort. You've got to be in shape physically with no injuries whatsoever.  Mentally you have to be at your peak at all times. It's not as easy as it seems sometimes." 

Federer remains one of the few players capable of troubling Djokovic, as he showed when he ended the Serb's 23-match winning run with a straight sets victory in the group stage of this year's Tour Finals. 

While he was unable to repeat that performance in the final, and also lost the Wimbledon and US Open finals to Djokovic, the 34-year-old is adamant he doesn't need to change much in his game to wrestle the major trophies away from the world number one. 

Asked if he needed to alter hs style of play in a bid to subdue Djokovic, Federer said: "Not really because I feel I need to work on my overall game that is going to have an impact against most players. 

"For me Rafa is the unique player in the field. I used to work more precisely against him. 

"With Novak it's more straightforward. If you don't play very well you are going to have a hard time. If you play better I know I have my chances with my game."

Federer will now head off to recharge his batteries and plan a fresh assault on Djokovic in 2016. 

As ever, winning another Wimbledon title is high on his list of priorities and he will also target a gold medal at the Rio Olympics.

"Wimbledon is a big one. Rio as well but it's not my number one priority. It starts with the Australian Open which is just around the corner," he said.

"Once that's over then I look more towards the future. 

"I don't think there's that much I need to change, other than a few tactical things against certain players at some times. I had a lot of great things in my game this year."

(File photo: ATP World Tour)