Top-seed Serena Williams' challenge for a sixth Wimbledon singles title fizzled out with a shock 1-6 6-3 6-4 defeat by France's Alize Cornet.
The 32-year-old American was untroubled in the first set but her game disintegrated as 25th seed Cornet took control in front of a stunned crowd on Court One.
Persistent rain at the All England Club meant only two games were possible when play started and when the players returned four hours later it was Williams who looked determined to make up for lost time with some powerful tennis.
The 24-year-old Cornet refused to fade away though and with Williams looking uncomfortable moving on the grass she took the second set with some accurate shot-making.
A desperate-looking Williams dropped serve at 2-2 in the decider and then again two games later and Cornet held her nerve to reach the last-16.
Earlier, Maria Sharapova won the last 11 games to reach the fourth round at Wimbledon with a 6-3, 6-0 victory over 44th-ranked Alison Riske of the United States.
Sharapova, the 2004 Wimbledon champion, got broken in the first game and fell behind 3-1 before overwhelming her opponent.
Saturday's match was played with the roof closed on Centre Court, while rain held up play on the outside courts.
Sharapova, who won the French Open earlier this month, lost in the second round at Wimbledon last year.