LONDON — For 34 matches over 4½ months, on hard, clay or grass courts, Serena Williams was unbeaten — and, in the minds of many, unbeatable.
So it was apt, somehow, that the longest winning streak in women's tennis since 2000 would end at this memorably unpredictable edition of Wimbledon, where up is down, where seedings and pedigree mean nothing whatsoever, where even five-time champion Williams looked lost at the start and, most surprisingly of all, the finish of her fourth-round match.
Stumbling on the Centre Court grass a couple of times while her game slumped in crunch time, the No. 1-ranked and No. 1-seeded Williams dropped the last four games to bow out 6-2, 1-6, 6-4 Monday against 23rd-seeded Sabine Lisicki.
"Didn't play the big points good enough," said Williams, who had won three of the past four Grand Slam titles, including Wimbledon a year ago and the French Open less than a month ago. "I didn't do what I do best."
Oddly passive down the stretch, Williams essentially let Lisicki do what she does best: dictate points quickly with a big serve, powerful returns and pinpoint groundstrokes. If that sounds familiar, could be because it's the formula Williams uses to dominate her sport. Except on this breezy afternoon, Lisicki compiled a 10-7 edge in aces, a 35-25 lead in winners, and broke Williams five times.
"Come on, guys, let's get with it. She's excellent," a composed Williams said at her news conference after blowing leads of 3-0 and 4-2 in the third set. "She's not a pushover."
Especially at Wimbledon. Her game is built for grass. Lisicki is a mediocre 16-15 at the other three Grand Slam tournaments and 17-4 at the All England Club. She reached the semifinals at Wimbledon in 2011, and is into her fourth quarterfinal, coincidentally beating the reigning French Open champion every time: Svetlana Kuznetsova in 2009, Li Na in '11, Maria Sharapova in '12, and Williams in '13.
"Good omen," Lisicki said. "Obviously I went into the match feeling that I could win."
Might have been the only person who felt that way. Williams, 31, owns 16 major championships and entering Monday, she had won 46 of 48 matches this season, and 77 of 80 since the start of Wimbledon in 2012.
Williams' departure made 17th-seeded Sloane Stephens the lone American singles player left. Her first quarterfinal at the All England Club comes today against No. 15 Marion Bartoli, the 2007 runnerup.
The other matchup in their half of the draw is No. 8 Petra Kvitova, the 2011 champion, against No. 20 Kirsten Flipkens.
Kaia Kanepi, ranked 46th, reached her fifth Grand Slam quarterfinal, and second at Wimbledon, with a 7-6 (8-6), 7-5 victory over 19-year-old Laura Robson, the first British woman in the fourth round at the All England Club since 1998.
On Wednesday, the men's quarterfinals include No. 1 Novak Djokovic, the only remaining past Wimbledon winner, against No. 7 Tomas Berdych. The bottom half of the draw includes No. 2 Andy Murray against 54th-ranked Fernando Verdasco; and No. 24 Jerzy Janowicz against his Davis Cup teammate and pal, 130th-ranked Lukasz Kubot, in a match between the first two Polish men to reach a Grand Slam quarterfinal since 1980.
One will give the country its first male semifinalist at a major tournament. Both benefited from one of the record-equaling 13 withdrawals or midmatch retirements last week.
"Everyone was a bit on edge, a little bit uptight, because of what was happening with the injuries, withdrawals, upsets and stuff," said Murray, who like Djokovic hasn't lost a set. "Obviously, Serena losing today is a major shock, as well."