( 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 ca n'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 .
Defending champion Serena Williams cruises into the fourth round at CNN . World No . 1 will next play Maria Sharapova , who beat her in the last 16 final . fourth seed Serena Williams also progresses into last 16 of grass-court grand slam . Italian 10th seed Maria Sharapova and No . 14 Victoria Azarenka of Belarus crash out .