LONDON -- All of a sudden, Serena Williams is failing to stick around for long at Grand Slam tournaments.
Betrayed by her backhand and, more surprisingly, her usually dangerous serve, five-time Wimbledon champion Williams lost to 25th-seeded Alize Cornet of France 1-6, 6-3, 6-4 Saturday in the third round at the All England Club.
"If I'm not playing a great, great match, these girls, when they play me, they play as if they're on the ATP Tour, and then they play other girls completely different," Williams said, rolling her eyes. "It's never easy being in my shoes."
It's her earliest exit at the All England Club since 2005, when she also was beaten in the third round. Williams won the title in 2002, 2003, 2009, 2010 and 2012.
"I don't know how I did it," Cornet said. "Just with my heart -- and the help of the crowd."
The No. 1-ranked and No. 1-seeded Williams owns 17 Grand Slam titles, one fewer than Martina Navratilova and Chris Evert, but she now has departed before the quarterfinals at four of the past five majors. There were fourth-round losses at Wimbledon last year and at the Australian Open in January, and a second-round loss at the French Open in May.
"Australia, I just couldn't play. And Paris I played really bad. Here, I actually thought I played better," she said. "I'm going to have to watch this film."
Cornet also beat the 32-year-old American at the Dubai Championships in February. Still, this result was rather unexpected, given their Grand Slam careers. Cornet never had been past the third round at Wimbledon, and she only once before reached a major's fourth round, in 2009.
Saturday's match was halted in the third game because of rain. After a delay of about 4½ hours, Williams was terrific, reeling off five games to grab the first set.
Things changed dramatically. Cornet began putting shots right where she wanted them, while Williams had trouble finding the mark. Williams wound up with 29 unforced errors, 11 more than Cornet.
"She helped me a little bit," Cornet said.
Two particular strokes troubled Williams: Her serve let her down repeatedly, with a total of seven double-faults and five breaks; her backhand produced 12 unforced errors.
In the third set, Cornet led 5-2 but was broken serving for the match. On her second chance, she steadied herself, delivering a perfect drop shot on match point.
When Williams netted the response, Cornet pounded her chest with her fist. Then she hopped around Court 1, before kneeling to kiss the grass.
Cornet had been 0-13 against top-20 opponents in Grand Slam matches.
"I don't really know what I did wrong," said Williams, whose sister Venus lost Friday. "Usually I do. Usually I know I did this, this, and that."
It was by far the most significant -- and surprising -- outcome on a day full of starts-and-stops thanks to the wet weather.
Unfettered by the rain because of the roof over Centre Court, Maria Sharapova won the last 11 games to reach the fourth round with a 6-3, 6-0 victory over 44th-ranked Alison Riske of the United States.
Sharapova, the 2004 Wimbledon champion and winner of the French Open earlier this month, was broken in the first game of the match, fell behind 3-1 then shut out Riske the rest of the way, clinching the match with a stinging forehand passing shot.
"I felt better as the match went on," said Sharapova, who lost in the second round at Wimbledon last year. "Alison's a great grass-court player. She's had some of her best results on this surface, so I knew that it was going to be a challenge today. I had a little bit of a slow start.
"I'm just happy to be in the second week after last year's result. I wasn't satisfied. I was looking forward to coming back very soon and here I am, giving myself another chance."
Third-seeded Simona Halep reached the Round of 16 at Wimbledon for the first time in her career, beating Belinda Bencic, 6-4, 6-1.
Sharapova will next face No. 9 Angelique Kerber. Cornet, meanwhile, takes on No. 13 Eugenie Bouchard, a 20-year-old Canadian who was a semifinalist at the year's first two majors.
"It shows all of you who asked me if I'm ready to play Serena in Round 4," Bouchard said. "That's one of the reasons I don't look far ahead."
Sunday is a scheduled off-day at Wimbledon, the only Grand Slam tournament that takes a break midway through.