Andy Roddick whipped a winner on the run past Lleyton Hewitt, raised his arms and yelled to celebrate, then basked in the standing ovation.

Exactly the sort of stuff Jimmy Connors used to do to fire up U.S. Open crowds, right? Roddick, now coached by Connors, capped a busy day at Flushing Meadows by beating fellow former champion Hewitt 6-3, 7-5, 6-4 Wednesday night to reach the semifinals for the first time since he won the tournament in 2003.

"Well, I guess I can play tennis a little bit again," Roddick said. "I'm in a little bit of shock. It's been a rough six months for me. I haven't played too well."

And there was more good news for Roddick: He won't have to play Rafael Nadal next. The second-seeded Spaniard was upset by 54th-ranked Mikhail Youzhny of Russia 6-3, 5-7, 7-6 (5), 6-1, meaning Nadal and No. 1 Roger Federer will not become the first pair of men to meet in three consecutive Grand Slam finals during a season.

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"Unbelievable," Youzhny said. "I cannot believe I beat Rafa in four sets."

A day after rain allowed only one match to finish, there was plenty of action. Federer and No. 5 James Blake set up a quarterfinal showdown with straight-set wins, and that half's other quarterfinal will be No. 7 Nikolay Davydenko against No. 14 Tommy Haas.

While Federer-Nadal III is no longer possible, there still could be a No. 1 vs. No. 2 final for the women, because top-seeded Amelie Mauresmo and Justine Henin-Hardenne advanced with relative ease.

Henin-Hardenne's 6-4, 6-4 win over Lindsay Davenport means this is the first year in the Open era — which began in 1968 — that no American woman reached any Grand Slam semifinal.

Mauresmo beat No. 12 Dinara Safina 6-2, 6-3 to move a step closer to her third Grand Slam title of 2006. Her next opponent is No. 3 Maria Sharapova, whose shrieking during her 7-6 (4), 7-6 (0) quarterfinal victory got to No. 27 Tatiana Golovin.

"It is kind of distracting. You don't need to be screaming that loud," Golovin said. "I don't think the ball actually goes faster if she's grunting."

Is Sharapova aware her grunts fluster foes?

"I don't worry about it," she said.

Henin-Hardenne's semifinal opponent is No. 19 Jelena Jankovic, who won Tuesday.

With Connors looking on in a blazer and tie, clapping occasionally, Roddick turned his big match against 2001 Open champion Hewitt into a mismatch. Hewitt came in with a 6-2 edge in career meetings, 3-0 at majors, but this isn't the same Roddick.

"That was a mentally tough match for me. Lleyton's gotten the best of me, especially in the bigger situations before. It was a big mental hurdle," Roddick said.

In just a few weeks of work, five-time Open champion Connors has given Roddick a ton of confidence, in addition to encouraging him to be more aggressive. Roddick pounded 17 aces against Hewitt, considered the game's top returner, and compiled a 46-28 edge in winners.

"He came out serving so well at the start," Hewitt said. "You're sort of up against it from the word, 'Go,'" Hewitt said.

Most significantly, Roddick showed new wrinkles, such as a two-fisted backhand that earned some key points, and the gumption to serve-and-volley on second serves. He saved three of four break points he faced and returned well, too, going 4-for-4 on his break chances.

Those are the kinds of things Roddick didn't do when he was stunned in the first round of last year's U.S. Open, or the third round of this year's Wimbledon. Or briefly slipping out of the top 10. Or going 10 months without a title, a drought snapped a week before the Open at the Cincinnati Masters — with Connors in his corner.

"It's a different way of playing. It's a new chapter," Roddick said. "I spent too much time this year — and I think everybody has — looking back. What's done is done. I need to focus on what I need to do to improve every day."

Now the ninth-seeded Roddick will deal with Youzhny, who added a second upset Wednesday, teaming with Leos Friedl of the Czech Republic in men's doubles to knock off the defending champions and top-seeded pair of American twins Bob and Mike Bryan 6-7 (5), 7-6 (2), 6-4 in the third round.

Youzhny never before had been beyond the fourth round in singles at a major tournament, and he acknowledged he didn't really expect to do it here. What was most remarkable was the way Nadal succumbed at the end, hanging his head at changeovers in the fourth set after wasting a 5-4 lead in the tiebreaker.

"I am trying to fight, but I wasn't," Nadal said. "I was not my best in the fourth, no? I know I lost a big opportunity. And after that, Mikhail is playing unbelievable ... all winners."

Youzhny displayed the sort of aggressive and on-the-mark shotmaking he used to knock off No. 6 Tommy Robredo, No. 11 David Ferrer and No. 19 Dominik Hrbaty earlier in the tournament. Before facing Robredo, Youzhny had lost 10 matches in a row against players in the top 10. Before Wednesday, he was 0-6 against players at No. 1 or 2.

But his high-risk style worked to perfection against Nadal. Youzhny compiled more than twice as many winners as Nadal (49-23), limiting Nadal to one in the fourth set.

Youzhny said he needed to play smart to beat Nadal.

"If you play like 'boom-boom,' like a lot of players do, I have no chance," he said.

Federer, meanwhile, is aiming for his ninth major title and third in a row here. He won the first 12 points en route to a 6-3, 7-6 (2), 6-3 victory over Marc Gicquel. Blake saved all 15 break points he faced and eliminated No. 12 Tomas Berdych 6-4, 6-3, 6-1.

"If I play my best, then I don't see any reason why I can't win. If he's playing his best, then I can see a reason why I might not win, but it's possible," said Blake, trying to reach his first major semifinal. "He's lost before. He is human."

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