WIMBLEDON, England ? Defending champion Roger Federer extended his grass-court winning streak to 21 matches Monday, setting up a showdown with 2002 winner Lleyton Hewitt in the Wimbledon quarterfinals.

In a match featuring only one break of serve, Federer beat 6-foot-10 Ivo Karlovic of Croatia — the tallest player in the game — 6-3, 7-6 (3), 7-6 (5). Federer hasn’t been broken or dropped a set all tournament.

Hewitt lost his first set of the championships but overcame ninth-seeded Carlos Moya, 6-4, 6-2, 4-6, 7-6 (3).

“I believe I can beat him,” Hewitt said of Federer. “It’s going to be an extremely tough match. He’s the best player out there at the moment. He’s not No. 1 for nothing.”

Second-ranked Andy Roddick, meanwhile, continued his own run to the quarters without the loss of a set, defeating unseeded Alexander Popp, 7-5, 6-4, 6-4.

Roddick needed five match points, finally closing it out with a forehand passing shot. He raised his arms, tipped his cap and saluted the Court 1 crowd. Roddick had 14 break points, converting four. Popp — a two-time quarterfinalist here — broke Roddick twice.

Roddick credited his improved service return for the victory.

“I broke him three times in the third set,” he said. “I’m not sure if I would have done that two years ago.”

The day ended with Tim Henman holding off Mark Philippoussis — last year’s runner-up — 6-2, 7-5, 6-7 (3), 7-6 (5), in a 3-hour, 7-minute match. Henman, bidding to become the first British player to win the men’s title since 1936, reached the quarterfinals for the eighth time in nine years. He has lost four times in the semifinals.

Andy Roddick returns a shot to Alexander Popp during their singles match at Wimbledon. Roddick won, 7-5, 6-5, 6-4, Monday in Wimbledon, England.

In women’s play, former champion Lindsay Davenport reached the quarterfinals with a 6-4, 6-4 win over Vera Zvonareva. Also advancing were two of the game’s most promising teenagers — 17-year-old Maria Sharapova and 19-year-old Karolina Sprem — and Japan’s Ai Sugiyama.

Davenport, the 1999 champion, reached the quarters for the seventh time in 11 appearances. She’ll next face Sprem, who beat Magdalena Maleeva, 6-4, 6-4. Sprem beat Venus Williams, a former two-time champion, in the second round last week.