World No. 1 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 yesterday's draw for the season finale.

The Swiss, who is 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 Centre alongside the River Thames when play starts on Sunday.

Rafael Nadal, who missed last year's finals in Shanghai, appears to have the easier draw as he tries to topple Federer from the world No. 1 spot.

The Spaniard, who beat Federer in the Australian Open final, will play Serbia's world No. 3 Novak Djokovic, Russian Nikolay Davydenko and Swede Robin Soderling, who ended Nadal's reign at the French Open this year.

Soderling, beaten in the French Open final by Federer, replaced American Andy Roddick who withdrew from the event with a knee injury.

Soderling will be the first Swede to play at the season finale since former Australian Open champion Thomas Johansson in 2002.

Argentina's Del Potro stunned Federer at Flushing Meadow 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.

One million pounds (US$1.68 million) is up for grabs if a player wins the title in London undefeated -- more than the 850,000 pounds Federer collected for winning Wimbledon this year.

London is beginning a five-year stint as host of the ATP Tour finals, with more than 255,000 tickets already sold for the eight-day event.

"There is a huge appetite in London for this tournament and it hopefully will put to bed the idea that tennis in this country is a two-week interest around Wimbledon," tournament director Chris Kermode said, who is also promising plenty of razzamatazz. While Wimbledon is well-known for its gentile Englishness, next week's events is aimed at a younger generation with rock music and lights adding to the entertainment.

The players will travel from their hotel to the venue by boat.

"We chose the hotel purely for its river access because the traffic in London is so unpredictable," Kermode said. "We have two 62-seater boats, they are smoother than a car and they will have the players door to door in 30 minutes. It's a really nice way for the players to see London.

"Some of the players are wondering what it's going to be like and they might opt to take the car once but I'm sure they'll soon realize that the boat is the best way to go."