Lleyton Hewitt turns back the clock to stun Juan Martin del Potro

Less than two years after surgery left his career in limbo, Lleyton Hewitt upset No. 6 Juan Martin del Potro at the U.S. Open. (Clive Brunskill/AP)

NEW YORK -- It doesn't matter the venue, the occasion or the opponent. Lleyton Hewitt, now 32 years old and ranked No. 66, will scratch and claw and battle with the best of them.

Hewitt upset sixth-ranked Juan Martin del Potro 6-4, 5-7, 3-6, 7-6 (2), 6-1 on Friday night at Arthur Ashe Stadium to advance to the third round of the U.S. Open. This marked the Australian's first victory over a top-10 player here since he won the tournament in 2001.

Del Potro, 24, was coming off a strong performance in the hard-court tune-ups after his run to the Wimbledon semifinals, winning the Citi Open and making the semifinals at the ATP Masters 1000 tournament in Cincinnati. But after playing a four-hour, three-minute match in his opening round, del Potro's energy reserves were low against Hewitt. He was also struggling with pain in right wrist. As del Potro went to his backhand slice more and more, Hewitt smartly began to exploit that wing to get the rallies on his terms and neutralize del Potro's aggression. While Hewitt played a clean match, hitting 42 winners to 43 unforced errors, del Potro hit 41 winners to 70 unforced errors.

"Well, the wrist is not the way that I'd I like, but what I say is not [an] excuse," del Potro said. "Now I have a few days to rest, to fix my wrist again, then see in which tournament I will play next."

The key to the match was the fourth-set tiebreak, which Hewitt played flawlessly. Playing to keep his tournament alive and force a fifth set against a weary del Potro, Hewitt nailed passing shot after passing shot as del Potro tried to be aggressive and shorten points.

"I didn't put a foot wrong in the tiebreak," Hewitt said. "Obviously, playing a tiebreak to stay in the tournament, it's always a tough position to be in. You never want to get down in that breaker. It was good to get the lead."

Once Hewitt took the tiebreak decisively, the errors came more frequently from del Potro. In total, the 2009 U.S. Open champion spent a total of eight hours and 16 minutes on court over the last 48 hours. Pushing the match into a decisive fifth set, Hewitt knew he had the edge.

"If I can take guys to five sets, I know it's slightly in my favor sometimes, I think," Hewitt said. "Especially against some of these bigger, stronger guys who can go out there and try and hit me off the court in three straight sets.

"I felt comfortable going into the fifth. And the way my body's been, I've been able to do a lot more training and a lot of other stuff, which I couldn't do a couple years ago because I was in too much pain."

For Hewitt, being scheduled for a night match on Arthur Ashe Stadium was a special treat. The Aussie isn't one to delude himself about the longevity of his career.

"I don't know how many times I'm going to play here in the future," Hewitt said. "You never know if you're going to get an opportunity to play out there again. I didn't take it for granted out there tonight.

"It's an amazing feeling. For me, just going back in the locker room afterward I sort of had to pinch myself. Yeah, I keep going back to it, but a year-and-a-half ago I got told I probably wouldn't play again with the surgery I had. For me, I love being out in that atmosphere, sucking up every second of it."