Novak Djokovic may have made a nervy start, but his win over Roger Federer shows why he'll soon be world number one again, says Greg Rusedski.
The Serbian, who lost his place at the top of the tennis world rankings to Rafael Nadal in October, beat six-time ATP World Finals winner Roger Federer 6-4 6-7 6-2 in an epic two hours and 22 minute match at the O2 on Tuesday night.
Djokovic now tops Group B ahead of Juan Martin Del Potro, Federer and Richard Gasquet and Sky Sports tennis expert Greg Rusedski believes the Australian Open champion will win the group and ease his way to the semi-finals.
"The first two sets were very nervy from both players in my opinion," said Rusedski,
"Djokovic showed us why he is number two at moment and will be number one again pretty soon in the coming year because he can just relax and find a way physically.
"For Federer, it's going to be difficult I think, because Del Potro has played better than Roger did on Tuesday night and that's going to be the big match to decide who gets through.
"the At moment I'm tipping Djokovic and Del Potro to top this group, Federer has to lift his game."
No need to worry
Despite the loss, Federer attacked Djokovic's game and pushed him in the first two sets. Boris Becker told Sky Sports that is was some of the best tennis he'd seen from the Swiss star in a long time.
"It was two of the best sets I've seen from Federer all year," he said.
"He faced the player of the moment, a player that hasn't lost a match since early September.
"When Federer drops just 10 per cent - that's not good enough anymore against Djokovic, Nadal or Murray; If Federer gives 100% like he did in the first two sets he's capable of beating anybody on any surface."
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