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By Toby Davis
LONDON, July 1 (Reuters) - Juan Martin Del Potro's battered body muscled into the Wimbledon quarter-finals on Monday, but the Argentine has only two days to recover from troublesome injuries before facing the endurance man of tennis in David Ferrer.
The eighth-seed powerfully dispatched Italy's Andreas Seppi 6-4 7-6(2) 6-3, but his knee was heavily strapped following a nasty fall in his third-round match.
His movement looked tentative and at times slightly cumbersome, but his big hitting ensured he had few problems against the 28th-ranked Seppi.
"The ankle is good and the knee is not good," he told reporters. "But I'm allowed to play.
"The doctor says it's nothing too dangerous, and that's positive.
"It bothers me a lot. I couldn't extend the knee 100 percent. And the tapes for today help me to be careful in some movements. But it's not enough.
"But I have a day and a half until my next match and I will do all the treatments to see if I can be better."
Against Seppi, he was able to generate sufficient power from his racket to leave his opponent flailing.
He broke in the seventh game of the first set before wrapping it up in 52 minutes, stayed solid to come through the second in a tiebreak, before breaking in the second game of the third set to effectively end the Italian's resistance.
It was all over in two hours and 22 minutes, leaving Del Potro free to hit the ice bath.
He is unlikely to get any respite from Ferrer, who holds a 6-2 winning record against him and is one of the tour's most punishing opponents, renowned for his never-say-die approach.
Ferrer came through a four-set last-16 clash against Croatia's Ivan Dodig and Del Potro, with little chance of outlasting the Spaniard, will hope his greater power can give him the advantage against a player who beat him at Wimbledon 12 months ago.
"I think he is number three in the world after this tournament. He deserves to be there, for sure," Del Potro said.
"He is a good player on grass. When you check the papers or you see Rafa and the rest of the Spanish guys, you say they are better on clay. But David, he is a very good player on all surfaces." (Editing by Ed Osmond)