The Associated Press

WIMBLEDON, England - Defending champion Roger Federer overcame 2002 winner Lleyton Hewitt in four sets Wednesday to reach the Wimbledon semifinals, edging closer to a possible final against Andy Roddick.

Federer lost his serve and dropped a set for the first time this tournament but had 19 aces and 50 winners to prevail 6-1, 6-7 (1), 6-0, 6-4 in a Centre Court match that ended close to dusk. It was Federer's 22nd consecutive win on grass.

The 2-hour, 19-minute match ended with a double fault by Hewitt.

Roddick, who hasn't lost a set in five matches, served 18 aces and outslugged Sjeng Schalken 7-6 (4), 7-6 (9), 6-3 - closing the match with a leaping overhead.

"The power Andy has, the ball's coming at you - you don't have any time to react," the 12th-seeded Schalken said. "That's something very special. He doesn't have a weakness, I think."

Roddick, seeded No. 2, advances to meet Mario Ancic, who upset fifth-seeded Tim Henman 7-6 (5), 6-4, 6-2. Roddick is 1-0 against Ancic, winning in three sets on grass at Queen's Club last month.

Federer will face Sebastien Grosjean, who swept Florian Mayer 7-5, 6-4, 6-2 to reach the semis for the second straight year.

The Federer-Hewitt match, interrupted twice by rain, featured a contrast between the all-court Swiss player with a big serve and the hustling Australian baseliner with a fantastic return.

"The first and third sets don't show how hard the battle was," said the top-seeded Federer, who seemed on his way to an easy win after breaking twice in the first set and serving it out with three aces.

But Hewitt lifted his game in the second set and dominated the tiebreaker, capitalizing on a terrible miss by Federer on a forehand sitter on the second point. Hewitt closed the tiebreaker with a second-serve winner, handing Federer his first set loss of the tournament.

Federer responded by winning seven straight games to go up two sets to one and 1-0 in the fourth. Hewitt took an injury timeout after the third set, receiving treatment on his right thigh, but never seemed troubled on the court.

After going 0-8 on break points, Hewitt broke for 4-3 - the first time Federer had been broken in 70 service games this tournament and in 105 games dating to last year's quarterfinals.

Unshaken, Federer broke back in the next game. Hewitt held two more break points in the following game, but Federer saved the first with an ace and the second with a service winner and held for 5-4. He broke Hewitt for the seventh time to end the match.

"He really stepped it up," Hewitt said. "He's the best player in the world at the moment."