|Nadal defeated Del Potro 7-6 , 3-6, 7-6 , 6-4 after squandering two set points in the 10th game [Reuters]
Rafael Nadal overcame an aching left foot to reach the quarterfinals at London's Wimbledon with a win over Juan Martin del Potro.
The dramatic first set, which saw the defending champion warned by umpire Carlos Ramos for taking too long between points, ended with him needing a medical time-out on Centre Court for a left foot injury at 6-6.
The 24-year-old had his foot bandaged while he sat in his chair, grimacing with pain, but still came out for the tie-break which he won even though his movement appeared to be restricted.
"I don't know what the problem is, it seems to be a problem with the bone in the foot," Nadal said after Monday's win.
"I thought I would have to retire at the end of the first set because there was a lot of pain. But the tape changed the situation. Now I will have to check with the doctors and the physios. Something is there."
Nadal, who had squandered two set points in the 10th game, had made Del Potro angry over the the amount of time spent on the attention paid to the Spaniard's injury.
A fired-up Del Potro then hit back to level the match, clubbing his way to the tie's first break in the eighth game of the second set.
The 22-year-old, who defeated Nadal for the loss of just six games in the US Open semi-finals in 2009 before he went on to clinch his first and only Grand Slam title, had never got beyond the third round here in three previous visits.
He missed last year's Wimbledon after a wrist injury, which restricted him to just three events and sent his ranking tumbling from four in the world to 485 in January.
He is back at 21 now and was using his giant 1.98m frame to hit deep and long on Monday. But at 2-2, 15-30 in the third set, it was Del Potro's turn to suffer when he hurt his left hip in a nasty fall as he tried to switch direction to chase down a Nadal forehand on the baseline.
The Argentine, who had suffered a similar injury in Madrid in May, then left the court for a medical time-out before returning to the fray.
He kept swinging in the third set but was out-played again in the tie-break which he conceded with a tame forehand into the net.
Nadal broke Del Potro for the first time in the match to lead 3-2 in the fourth set and took the victory on his first match point when Del Potro went long with a lob.
Roger Federer, the six-time men's champion, survived a scare, dropping his first set of the tournament before coming back to down Mikhail Youzhny 6-7 (5), 6-3, 6-3, 6-3 to reach his 29th successive Grand Slam quarterfinal.
Extending his career record against the Russian to 11-0, Federer had 54 winners, including 14 aces, and broke five times.
"I forgot completely [the 29th quarterfinal] was on the line to be quite honest, especially once you're in the heat of the moment, of the battle,'' Federer, who also won his 100th match on grass, said.
"I thought I played a good match overall.''
Federer will next face No. 12 Jo-Wilfried Tsonga of France, who beat No. 7 David Ferrer 6-3, 6-4, 7-6 (1).