Argentina's Juan Martin Del Potro celebrates winning his
men's singles tennis match against Switzerland's Roger
Federer at the ATP World Tour Finals at the O2 Arena in
London. REUTERS/Stefan Wermuth
Juan Martin del Potro has beaten Roger Federer 7-6 4-6
6-3 to reach the semi-finals of the ATP World Tour Finals in
The Argentine guaranteed himself one of the top two places in
Group B with a 2-1 record, the same as defending champion
Federer, who had already sealed a semi-final spot after
winning his opening two round-robin matches at the
The final day of action in Group B began with seven
scenarios, but a three-set win for world number seven Del
Potro muddied the waters as the line-up for the semi-finals
will now not be known until after the evening match between
David Ferrer and Janko Tipsarevic.
Victory for Tipsarevic would see Del Potro top the group,
while a win for Ferrer would mean three players are tied on
two wins and in that case Federer would top the group because
of his superior sets percentage and Del Potro would be
Ferrer had been relying on a Federer victory to keep his
hopes of a semi-final place alive.
The winner of the group will face Britain's Andy Murray while
the runner-up will play world number Novak Djokovic.