Roger Federer predicts closest Tour Finals ever

ROGER Federer is adamant the line-up for next week's ATP World Tour Finals in London is the most competitive it's ever been.

CLOSE SHAVE: World number one Roger Federer is predicting a tough battle in London but hopes to keep top ranking with a win (Getty Images)

After being displaced as world number one by Rafael Nadal last season, the Swiss maestro returned to the top of the game this year, completing his career grand slam at the French Open and reclaiming the Wimbledon crown.

But the season has also had its low points for the Fed Express, including an emotional defeat to Nadal in the Australian Open final and a shock loss to Argentina's Juan Martin Del Potro in the US Open final.

And Federer, who has lifted just two of the nine Masters 1000 trophies this season, admitted he was expecting this year's season-finale at the O2 to be closer than it's ever been.

"It's always a good field and last year was tough in Shanghai. And this year, both groups are going to be so tough," said Federer, who failed to progress past the round robin stage 12 months ago.

"Everyone has had big moments this season and the top four has comprised the same people all year.

"But the other four guys have had some great results as well with Robin Soderling doing the unthinkable and beating Rafa in Paris and Del Potro playing so well to beat me at Flushing Meadows.

"So I think it could be really close again this year."

After slipping to world number three following his spell on the sidelines with tendinitis in his knee, Nadal is now closing in on the top spot again.

But Federer insists the knowledge that he could still end his season as world number two is the perfect incentive to reclaim the trophy he relinquished to Serbia's Novak Djokovic last year.

"I'm not going to lie and say I'm only here to play well," said Federer, who is vying for a record-equalling fifth Tour Finals success.

"I'm aware of the race to finish as world number one and obviously I'm here to make sure it's me who wins it.

"It's not going to be easy but it adds an extra angle to have the ranking on the line for the last tournament of the year.

"I'm just going to try my best and hopefully, win the tournament."

Federer kicks off his campaign against Spain's Fernando Verdasco on Sunday with British number one, Andy Murray, and Del Potro the other Group A players.

Meanwhile, Group B singles matches start on Monday with Nadal facing Soderling and Russian Nikolay Davydenko taking on Djokovic.