Del Potro stands up to Federer

NEW YORK -- SI.com caught up with Sports Illustrated senior writer Jon Wertheim after Juan Martin del Potro defeated Roger Federer to win the U.S. Open men's final 3-6, 7-6 (5), 4-6, 7-6 (4), 6-2.

SI.com: Were you surprised by the 20-year-old's win?

Wertheim: In a way, del Potro doesn't live in the Federer Era. He's eight years younger. I think that helps a bit in his approach. He was already a top six player coming into the Open, but he showed something that other elite players lack. Rafael Nadal stands up to Federer, and after that on the men's side, not so much. For del Potro to stare down Roger, fall down two sets to one and come from behind is almost more impressive than if he had just been in a zone like he was against Nadal. His stamina has been in question, so the way he won was rather stunning. One had to think that either Roger would bully him from the start and go on to win or you would have a situation like when Marat Safin upset Pete Sampras. I think we wound up getting a little bit of both. To win your first Slam by downing Nadal in straight sets in the semis and then Federer in five? That's not a road many go down and survive with the trophy at the end.

SI.com: Can his hard court success translate to Slams on other surfaces?

Wertheim: Thinking about it now, if he had played a few points differently in Paris, he could have been a two-time Grand Slam winner this year himself. The grass is always going to be a challenge for someone that big who still has some movement issues. I think the grass is a push. On three of the four majors, though, he's going to be a contender each time.

SI.com:Andy Murray fell quickly to Federer in last year's final, but was held up as next to win Grand Slam this season. Has del Potro surpassed him as the third best player in the world now?

Wertheim: Look at his results over the past 15 months -- from the summer-long win streak last year, the win over Andy Roddick in Washington. If he's not No. 3, he is No. 4. The depth of talent atop the men's game is unbelievable right now. Five of the top six have won major titles and Murray is right there as well.

SI.com: How lethal is del Potro's forehand?

Wertheim: It's like Roddick's serve at this point. Simply devastating. He can hit it on the run, angle inside-out motions and strike with consistency. James Blake has a strong forehand, but he needs to be able to lock and load. Del Potro's is more impressive in that he can summon the strength all over the court in a number of positions. It's almost a joke.

SI.com: Where is Federer's game now at the end of the year Slam-wise?

Wertheim: He wasn't devastated in defeat like he was in Australia. That's because he's in a different place now. Here's a guy who hadn't won a single tournament for the first five months, lost to Nadal in Australia, had some shaky matches, broke his racket and fell from being No. 1. Everybody wondered if the great reign finally ended. Then he resuscitated his career, winning the French for the first time, taking Sampras' record, got married, had twins and finished up here in the finals. He said the music at the Open calmed him, but he can close this year out knowing how far he came since Australia.

SI.com: Does del Potro have the Q rating to draw attention in American markets?

Wertheim: He's not as familiar to Americans as Melanie Oudin, but I thought he handled himself well. He'll be hurt -- like Nadal -- with language issues, but he seems genuinely happy with his success. The crowd behind him was great with its chants and flags. What worried me was that not everyone can get out of work at 4 p.m. on a Monday, but the atmosphere was great.