(CNN) -- Defending champion Serena Williams will face former winner Maria Sharapova in the fourth round at Wimbledon after both players progressed comfortably on Saturday.
World No. 1 Williams thrashed unseeded Slovakian Dominika Cibulkova 6-0 7-5 as she did not lose a game in the opening set for the third successive match.
Williams is seeking her fourth title at the grass-court grand slam in England, but said she has yet to find the form of last year despite an ominous start to the two-week tournament.
"I was playing a little better last year, so hopefully I can pick it up -- obviously I'll have to in the next match," the American told reporters.
"It's really intense when I play Maria. It's a great match-up and it's good for the tour that she has come back and is playing well. I'll have to play better if I'm to continue to do well.
"I could have played better in the second set today. I stepped off the gas a little too much, and you just can't afford to do that in big grand slams like this."
Sharapova, the 2004 champion, continued her comeback from long-term injury with an error-strewn 7-5 6-3 win over Barbora Zahlavova Strycova of the Czech Republic.
The former world No. 1, seeded 16th this year, made 35 unforced errors against a player ranked 68th in the world who has never made it past the third round at Wimbledon.
She beat Williams to claim the title as a 17-year-old, but has fallen down the rankings after a difficult past year.
"It'll be a really tough match. She's a defending champion and playing really well," the 23-year-old Russian told reporters.
The winner of the Williams-Sharapova tie will take on either Polish seventh seed Agnieszka Radwanska or Chinese No. 9 Li Na.
Radwanska won 6-3 6-1 against Italian 32nd seed Sara Errani on Saturday, while Na beat Australia-based Russian Anastasia Rodionova 6-1 6-3.
Third seed Caroline Wozniacki, who is in the same half of the draw, progressed into the last 16 with a 7-5 6-4 victory over Russian 29th seed Anastasia Pavlyuchenkova.
The 19-year-old Dane will next face unseeded Czech Petra Kvitova after the 20-year-old knocked out 14th seed Victoria Azarenka of Belarus with a 7-5 6-0 victory.
Italian 10th seed Flavia Pennetta also exited, losing 6-2 6-3 to Klara Zakopalova.
The unseeded Czech will appear in the fourth round of a grand slam for the first time when she takes on Estonia's Kaia Kanepi, who has never before been past the second round at Wimbledon.