Del Potro Qualifies for World Tour Finals Semis
World No. 7 Juan Martin del Potro qualified for the semifinals of the World Tour Finals with a three set win over World No. 2 Roger Federer, 7-6, 4-6, 6-3.
Del Potro joins Federer, Novak Djokovic, and Andy Murray, who have also qualified.
It was his second win of the year over Federer, improving his 2012 record to 2-6 against the World No. 2.
The semifinal match-ups will be determined by the winner of the match between David Ferrer and Janko Tipsarevic. If Tipsarevic wins, del Potro will play Murray and Federer will take on Djokovic. If Ferrer wins, del Potro will face Djokovic and Federer will play Murray.