WIMBLEDON, England - When Roger Federer misfired on animportant shot Friday, his knees buckled and he stomped behind thebaseline, miffed at his mere mortality.
The moment quickly passed, and Federer advanced to the secondweek at Wimbledon by beating Philipp Kohlschreiber 6-3, 6-2, 6-7(5), 6-1.
Federer lost a set for first time this week, with two errantforehands costing him the tiebreaker. That merely extended hisCentre Court workout by half an hour.
"It has been a good first week," he said. "Pretty convincing.I thought this was my best match of the tournament, even though Idropped a set."
Federer earned a berth in the fourth round Monday against afamiliar foe -- Robin Soderling. Federer beat Soderling in theFrench Open final this month to complete a career Grand Slam andwin his 14th major title, tying Pete Sampras' record.
Now the No. 2-seeded Federer seeks his sixth Wimbledon title,and he's a heavy favorite with defending champion Rafael Nadalabsent because of bad knees.
"It's down to business in the second week," Federer said."This is where it gets really interesting."
While Federer played on Centre Court, where the new retractableroof remained open for the fifth consecutive day, two-time championSerena Williams was assigned to Court 2 and arrived six minuteslate for her match. Otherwise Williams remained right on schedule,beating Roberta Vinci 6-3, 6-4.
Federer could have won more quickly. He converted only seven of22 break-point chances and led 4-2 in the third set, before the No.32-ranked Kohlschreiber played his best stretch of tennis.
Federer's rare display of frustration came after he pulled aneasy forehand wide trailing 5-4 in the tiebreaker. Two pointslater, Kohlschreiber ripped a backhand winner to force a fourthset, but Federer pulled away from there and extended his winningstreak to 15 matches, his longest in two years.
"Sure, I would have loved to win in straight sets, but he cameback strong," Federer said. "I was happy how I reacted. I didn'tpanic."
Soderling reached the fourth round for the first time in sevenappearances at Wimbledon by defeating Nicolas Almagro 7-6 (7), 6-4,6-4. The Swede lost only three points on his first serve and neverfaced a break point.
Up next: Federer. Soderling has lost all 10 of their matches.
"It's tough to play against Roger," Soderling said. "I'veplayed him 10 times, and after the match I never felt like I playedwell. But I mean, it's not because of me. I think it's because ofhim."
Unseeded Dudi Sela became the first Israeli man in 20 years toreach the fourth round when he beat No. 15 Tommy Robredo 7-6 (8),7-5, 2-6, 7-5. The 22nd-seeded Ivo Karlovic hit 46 aces, the laston match point, to upset No. 9 Jo-Wilfried Tsonga 7-6 (5), 6-7 (5),7-5, 7-6 (5).
In women's play, 19-year-old Victoria Azarenka made a successfulCentre Court debut by beating Sorana Cirstea 7-6 (2), 6-3. GiselaDulko, who upset 2004 champion Maria Sharapova in the second round,was eliminated by No. 10 Nadia Petrova 3-6, 6-3, 6-4.
Seventh-seeded Vera Zvonareva, slowed by an ankle injury sinceApril, pulled out before her match against No. 26 Virginie Razzano.Fourth-seeded Elena Dementieva, a semifinalist last year, cruisedpast qualifier Regina Kulikova 6-1, 6-2.
Williams' tardy arrival inspired brief speculation she might bea no-show. Once that ended, so did the prospect of an upset againstVinci.
Williams said she was late heading to the court at the south endof the club because she was awaiting an escort.
"I thought someone was going to come get me," she said. "Iwas waiting and waiting. Finally I was like, 'OK, I think I'm justgoing to go out.' I'm used to someone coming and saying, 'OK, let'sgo."'
The mix-up didn't rattle Williams, who hit 10 aces and committedonly 12 unforced errors to win for the 172nd time in 200 Grand Slammatches. The only other active woman to play so many matches inmajor tournaments is her sister, five-time Wimbledon champion Venus(219).
The No. 2-seeded Serena used her penetrating strokes to pushVinci around the court. One time the Italian scrambled to retrievea shot in the corner several steps beyond the lines, then stoodhelpless as Williams hit a winner into the other corner.
Williams' opponent in the round of 16 Monday will be DanielaHantuchova, who beat doubles partner Ai Sugiyama 6-4, 6-3. Williamsis 6-1 against Hantuchova.
"She's such a smooth player," Williams said. "I have to makesure I don't rush myself, because she is playing well, and I thinkshe's moving well. So I'm going to have to really bring a toughgame."