PARIS (AP) -- What started as a replay of a U.S. Open nightmare turned into something much better for Roger Federer: a trip to the French Open semifinals.
Federer overcame a two-set deficit for the seventh time in his career Tuesday for a 3-6, 6-7 (4), 6-2, 6-0, 6-3 victory over Juan Martin del Potro. The Argentine famously beat Federer in the final at Flushing Meadows in 2009, ending his 40-match U.S. Open winning streak.
The third-seeded Federer's victory Tuesday pushed him to his record-tying 31st Grand Slam semifinal. He'll play Novak Djokovic in the semifinals.
Del Potro, seeded ninth, said he'd need a nearly perfect day to reprise his upset over Federer from 2009, and for two sets he was on course. But Federer loosened up and rallied - including a steamroller fourth set in which he hit 13 winners and no unforced errors - and earned his record-extending 237th Grand Slam match win.
"Letting go helped me," Federer said. "I pushed harder at the end of the second set."
Del Potro, meanwhile, played with a heavily taped left knee and appeared to slow as the match went on.
He began the day by forcing the action, pushing Federer from side to side. He ended it on defense, trying simply to hang in there and hope for something to change the momentum - like a burst of match-stopping rain. But all he got was a sprinkle on Court Suzanne Lenglen when Federer served out the match.
Federer beat del Potro for the seventh straight time since that U.S. Open loss. One of those wins came this year in the Australian Open quarterfinals and there have been three more since, but all have come in straight sets without much drama.
This time, it seemed like a real possibility that Federer could lose. He looked tired and a bit sloppy (14 unforced errors) in the first set. In the second, Federer was serving down 5-4 in the tiebreaker, but del Potro drove him backward, off the court and forced misses off Federer's forehand side two times to wrap up the set.
Things changed dramatically and quickly, though. The third and fourth sets took a total of 55 minutes - only four fewer than entire second set. Federer got a break right away in the fifth set, then served it out.
Earlier in the day, in the women's quarterfinals, No. 6 Samantha Stosur defeated No. 15 Dominika Cibulkova 6-4, 6-1 and No. 21 Sara Errani made her first Grand Slam semifinal with a 6-3, 7-6 (2) victory over 10th-seeded Angelique Kerber.