LONDON-- Maria Sharapova has been knocked out of Wimbledon by a 131st-ranked qualifier on a day when injuries forced the withdrawal or retirement of seven other players.
The third-seeded Sharapova, the Wimbledon champion in 2004 champion, lost 6-3, 6-4 to Michelle Larcher de Brito of Portugal in the second round at the All England Club.
It's the second significant upset of the tournament, which is only in Day 3. Two-time men's champion Rafael Nadal was beaten on Monday by 135th-ranked Steve Darcis.
Sharapova slipped and fell several times on the grass on Court 2 and received medical treatment from the trainer in the second set.
The women's tournament also lost second-seeded Victoria Azarenka, who withdrew before her match with a knee injury. Sharapova and Azarenka had been considered the main challengers to five-time champion Serena Williams.
Playing with tape on her right ankle, former world No. 1 Caroline Wozniacki slumped to a 6-2, 6-2 defeat to Petra Cetkovska in the second round Wednesday.
The ninth-seeded Wozniacki, who has never fared very well on the London grass, is going through a mediocre season. She also lost in the second round at the French Open.
The 196th-ranked Cetkovska, who reached the fourth round at Wimbledon two years ago, erased the six break points she faced and hit 30 winners.
A qualifier from the Czech Republic, Cetkovska's 2012 was cut short after the London Olympics because of a right ankle injury. She returned this year and has nosedived in the WTA rankings.
Canadian teenager Eugenie Bouchard picked up the biggest victory of her career, beating 12th-seeded Ana Ivanovic, the 2008 French Open champion, 6-3, 6-3 to reach the third round.
The 66th-ranked Bouchard, who is 19, won the girls' title at the All England Club a year ago.
Playing in only her second Grand Slam tournament, Bouchard wound up on Centre Court on Wednesday, because her match against Ivanovic was moved there after second-seeded Victoria Azarenka withdrew with a knee injury, leaving a gap in the schedule.
Already leading 5-3 in the first set, Bouchard took 12 of 13 points to close that set and go up a break in the second.
In eight previous Wimbledon appearances, Ivanovic only once had failed to reach the third round.