WINSTON-SALEM, N.C. — Andy Roddick proved dominant again in the Davis Cup, sending the defending champion United States past France today and into the semifinals against Spain.

Behind a blistering serve, Roddick defeated Paul-Henri Mathieu 6-2, 6-3, 6-2 for the deciding victory in the best-of-five quarterfinal. This was Roddick's second singles victory in three days.

A day after a loss by the No. 1 doubles team of Bob and Mike Bryan kept France's hopes alive, Roddick was never threatened in giving the Americans an insurmountable 3-1 lead. While he was held to 17 aces, he lost only 13 points on his serve to improve to 10-0 in clinching situations for the U.S.

"I think everyone makes a big deal about the 10-0 thing," Roddick said. "I have to be up 2-1 in order to clinch, so I've been put in good positions a lot of times."

Roddick wrapped up the sixth straight Davis Cup victory for the U.S., including last year's win over Russia in the final, with an ace down the middle. He then made a lap around the court with the American flag and his teammates.

In a concluding singles match that had no bearing on the outcome, James Blake defeated Richard Gasquet 6-7 (4), 6-4, 6-4 for a 4-1 final score.

Next up for the U.S. is a road matchup against Rafael Nadal and Spain in the semifinals Sept. 19-21, which almost certainly will be on clay.

"I know it's not convenient for us. I know we're not going to be the favorites," Roddick said. "But I know we're going to go and we're going to try. The thing about this team is we don't play when it's convenient. That's probably different from some of the other countries."

In other quarterfinals, Russia eliminated the Czech Republic 3-2, and Argentina ousted Sweden 4-1. Spain advanced Saturday by defeating Germany and led 4-0 Sunday.

Roddick broke Mathieu five times and won in just more than 90 minutes. He had 30 aces in a straight-sets win over Michael Llodra on Friday and never faced a break point against Mathieu. Roddick wasn't broken in two matches on the quick, indoor hard-court suited to his style.

"I wasn't giving him anything," Roddick said. "The points he was winning he was having to step up and crank two or three balls to the corners and really execute his shots."

Roddick improved to 29-9 for the U.S. in Davis Cup matches, trailing only John McEnroe (41) and Andre Agassi (30). His win against the 12th-ranked Mathieu was part of an exceptional month in which he beat the tour's top three players — Roger Federer, Nadal and Novak Djokovic.

"He's playing on that kind of court, the court is very fast," Mathieu said. "He served pretty good today. For sure, he was tough to beat today. Andy played a great match."

France exited in the quarterfinals for the fourth straight year without its top lineup. Australian Open finalist Jo-Wilfried Tsonga flew back to Paris on Wednesday after an MRI exam revealed a cartilage tear in his right knee. Gasquet, the top-ranked Frenchmen at No. 10, was held out until Sunday's meaningless final match against Blake.

Gasquet didn't play in Friday's singles with a blister on his right hand and a sore knee. And even though Gasquet shocked Roddick in last year's Wimbledon quarterfinals, Gasquet apparently didn't want to play until the final match.

"That's the way he is," said Mathieu, who wasted two match points Friday before falling to Blake in five sets. "Maybe he didn't want to play Roddick, he didn't like his game. I don't know."

While the French were frustrated at not being healthy, Roddick's dominance may have made the point moot.

"I don't think it would have mattered, the way I played today," Roddick said.