Del Potro qualifies for Masters Cup

U.S. Open champion Juan Martin Del Potro of Argentina is the fifth singles player to qualify for November's ATP World Tour finals.

The 20-year-old, who beat world No. 1 Roger Federer in five sets for his first Grand Slam title on Monday, joins Federer, Rafael Nadal, Andy Murray and defending champion Novak Djokovic for the end-of-season event, according to an ATP statement.

Del Potro, who is ranked No. 5, will appear at the eight-man indoor tournament, which takes place in London from Nov. 22-29, for the second consecutive season.