US OPEN champion Sam Stosur and former world number one Caroline Wozniacki were major casualties on day three at Wimbledon.
Fifth seed Stosur was knocked out in the second round by Holland's Arantxa Rus. The Australian, who reached the semi-finals of the French Open earlier this month, fell to a 6-2 0-6 6-4 defeat.
Stosur battled back in the second set but then faded in the decider as she failed to progress beyond round two for the third consecutive year.
Wozniacki was another to make a surprise exit, in the first round in her case, as she was beaten by Austrian Tamira Paszek.
The seventh seed took the first set but then squandered two match points in the next, narrowly losing the second set before Paszek also claimed the third to win 5-7 7-6 (7/4) 6-4 in three hours and 12 minutes.
"It's not a nice feeling," Wozniacki said. "Especially after having two match points and not taking them.
"It wasn't that I played badly. She just went for them and that's it."
She will now be a surprise visitor at Royal Portrush to watch her boyfriend Rory McIlroy in action in the Irish Open.
Serbian Ana Ivanovic progressed to the second round with a hard-fought 6-3 3-6 6-3 win over Spain's Maria Jose Martinez Sanchez. The 14th seed prevailed after two hours on Court 14.
Heather Watson became the first British woman to reach the third round at Wimbledon for 10 years, as she put in a highly impressive display to overcome American Jamie Hampton.
The 20-year-old was full of confidence following her maiden win over Iveta Benesova and eased into the next round with a comfortable 6-1 6-4 win.
Third seed Agnieszka Radwanska swept into the third round with a comfortable 6-2 6-1 win over Russia's Elena Vesnina and is set to play Watson tomorrow.
Chinese 11th seed Li Na was a casualty in the second round after she lost 6-3 6-4 to Romania's Sorana Cirstea, while Julia Goerges eased into round three with a 6-2 6-2 win over Shahar Peer.
Germany's Sabine Lisicki was pushed all the way by Serbia's Bojana Jovanovski and had to come from a set down to win with a third-set tie break.
Lisicki, the 15th seed and a semi-finalist last year, complained about her opponent's grunting during the match but kept her focus to triumph 3-6 6-2 8-6.
Elsewhere, Ukraine's Kateryna Bondarenko defeated veteran Kimiko Date-Krumm 5-7 6-3 6-3.
Bondarenko held off the challenge of the 41-year-old Japanese player after she lost the 47-minute first set.
Kim Clijsters impressed in her second-round match against Andrea Hlavackova, winning 6-3 6-3.