LONDON - Roger Federer will face US Open champion Juan Martin del Potro, Andy Murray and Spain's Fernando Verdasco in the tougher of the two round-robin groups for the ATP World Tour Finals in the United Kingdom.

LONDON - Roger Federer will face US Open champion Juan Martin del Potro, Andy Murray and Spain's Fernando Verdasco in the tougher of the two round-robin groups for the ATP World Tour Finals in the United Kingdom.

Group B in the end-of-season showpiece event features former world number one Rafael Nadal, recent Paris Masters champion Novak Djokovic, Nikolay Davydenko and late entrant Robin Soderling, who had failed to qualify for the eight-man event but was brought in following the withdrawal of injured Wimbledon finalist Andy Roddick.

"There are no easy matches regardless of what group you're in," Murray said.

The top two in each group go to the final of the tournament that starts on Sunday at London's O2 Arena . - Sapa-AFP