Despite injury in his left foot, defending champion Rafael Nadal of Spain won 7-6 (6), 3-6, 7-6 (4), 6-4 over 2009 U.S. Open champion Juan Martin del Potro.
Doubt now hangs over the ability of top seeded Nadal if he will be able to continue for Wednesday’s quarterfinals.
The injury came as Nadal hit a forehand in the game before the first-set tiebreaker. With temporary medical first aid application on hand, he seemed not to be bothered with his injury, although he limped occasionally.
Nadal said he would undergo an MRI scan to determine the extent of his foot injury.
The men’s quarters will be played Wednesday, with Nadal vs. No. 10 Mardy Fish of the United States.
On the other hand, Federer lost his first set came back to defeat Mikhail Youzhny 6-7 (5), 6-3, 6-3, 6-3 to reach his 29th subsequent Grand Slam quarterfinal.
The six-time Wimbledon champion Roger Federer will play against No. 12 Jo-Wilfried Tsonga of France on the quarterfinal Wednesday.
Among those scheduled to play on Wednesday for Wilfred Tsonga, the quarterfinals are: Novak Djokovic against 18 year old Australian qualifier Bernard Tomic and the Briton Andy Murray against unseeded Spaniard Feliciano Lopez.