MONTREAL, Aug. 15 (UPI) -- Roger Federer, ranked first in the world, and Rafael Nadal, ranked second, became upset victims Friday in the quarterfinals of the Rogers Masters.
Federer, a two-time winner of the event, had a 5-1 lead in the third set before falling to Jo-Wilfried Tsonga 7-6 (7-5), 1-6, 7-6 (7-3).
In an evening match, Juan Martin del Potro ousted Nadal 7-6 (7-5) 6-1. Del Potro has beaten Nadal twice this year and the result spoiled Nadal's return after a two-month absence brought on by sore knees.
In the other two quarterfinal matches, Andy Roddick held off Novak Djokovic 6-4, 7-6 (7-4), and Andy Murray, the top seed remaining at No. 3, defeated Nikolay Davydenko 6-2, 6-4.
Roddick will face del Potro, and Murray will take on Tsonga in the semifinals.
Federer was playing in his first tournament since capturing a record 15th career major title last month at Wimbledon.