Roger Federer to face Del Potro and Murray in finals

World number one Roger Federer will face his US Open conqueror Juan Martin del Potro in the round-robin stage of the ATP Tour finals after getting the rough end of Wednesday's draw for the season finale.

The Swiss, still not guaranteed to end the year on top of the rankings, will also face Britain's Andy Murray and Spain's Fernando Verdasco in Group A at the eye-catching O2 Arena alongside the River Thames when play starts on Sunday.

Rafael Nadal, who missed last year's event in Shanghai and therefore has no ranking points to defend, has the easier draw as he attempts to topple Federer from the world number one spot.

The Spaniard, who beat Federer in the Australian Open final, will play Serbia's world number three and 2008 champion Novak Djokovic, Russian Nikolay Davydenko and Swede Robin Soderling, who ended Nadal's four-year reign at the French Open in May.

Soderling, beaten in the Roland Garros final by Federer, replaced American Andy Roddick who withdrew from the event on Tuesday with a knee injury.

Nadal trails four-times Tour Finals champion Federer by 945 points in the rankings but with 1,500 available for an undefeated champion next week he will arrive in London still hopeful of reclaiming the number one spot.

Argentina's Del Potro stunned Federer at Flushing Meadows in September, preventing the Swiss winning the title for a sixth consecutive year, and their meeting will be an intriguing contest, as will Nadal's re-match with Soderling.

Murray, who reached the semi-finals last year in Shanghai, said he relished the chance to take on Federer, a player he holds a 6-3 career lead over, in London.

"To get a chance to play against Federer, maybe Nadal here, the crowd is going to be great," the Scot, who attended the draw in a pod of the London Eye, Europe's tallest Ferris wheel, said.

"It's a great group of players, probably the strongest we've had in quite a few years. It's a tough group but if I play well I think I have a good chance of qualifying."

A prize money of £1 million pounds ($1.68 million) is up for grabs, if a player wins the title in London undefeated — more than the £8,50,000 Federer collected for winning his sixth Wimbledon title this year.

In the doubles draw American twins Bob and Mike Bryan were drawn in Group B while Daniel Nestor and Nenad Zimonjic, who the Bryans hope to dislodge as the world's top pair, head Group A.

London is beginning a five-year stint as host of the ATP Tour finals, with more than 2,55,000 tickets already sold for the eight-day event.