Rafael Nadal broke his own record to end the season as the oldest ever man to occupy the No 1 spot, finishing 840 points clear of Djokovic.

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Both men will have a sizeable points haul to defend in the early part of the season too, having contested the final of the Australian Open last year, which Djokovic won in straight sets.

And Ivanisevic reckons the world No 2 will not need any added motivation to reel in Nadal.

"You can see why he's won so many titles. He will now be even hungrier, finishing second," Ivansevic told Croatian publication Jutarnji.

"We have a phenomenal co-operation and a brilliant relationship. Mentality and a common language help a lot."

Djokovic has been working with Ivanisevic since last summer

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Djokovic finished the season with five titles to his name, his best haul since a series of surgeries on his right elbow, including the Australian Open, Wimbledon and two Masters 1000 tournaments.

The 32-year-old now has 16 Grand Slam titles to his name but is still three behind Nadal and four behind Roger Federer in a three-way battle at the top of the all-time list.

Even Federer, at the age of 38, looks no closer to retirement and says he will play every Grand Slam and the Olympics in 2020, a remarkable feat of longevity that former world No 1 Stan Smith puts down to the way he moves on the court.

Djokovic is still chasing down Federer's Grand Slam record

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"One of the keys I think for him is his balance," Smith said.

"He stays in good balance when he hits the ball and so it prevents him from being injured and it also makes him consistent and also enables him to recover much better after he hits a wide shot, for instance.

"He’s in such good balance, he doesn’t have to take an extra couple of steps to recover his balance.

"He hits the ball on balance even when he’s moving hard to get back into the point. That’s one of the reasons he’s been so effective."

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