Updated

Reigning world No. 1 Victoria Azarenka and Wimbledon champion Serena Williams were a pair of third-round winners, while Venus Williams exited the singles draw Wednesday at the Olympic Tennis Event.

The Belarusian Azarenka was pushed in a 7-6 (8-6), 6-4 victory over 16th- seeded Russian Nadia Petrova on Court 1, while the fourth-seeded former No. 1 Serena lambasted 13th-seeded Russian Vera Zvonareva 6-1, 6-0 on the famed Centre Court at the venerable All England Club.

Azarenka, who has spent the majority of 2012 at No. 1 after capturing her first major title at the Australian Open in January, will tangle with tough German left-hander Angelique Kerber in her next outing.

The Day-5 rout for Serena against Zvonareva was over in 51 minutes, as the powerful American fired 12 aces, did not commit a double fault, and struck 29 more winners (32-3) than her helpless Russian counterpart.

Serena also whipped the 2008 Beijing bronze medalist Zvonareva in a Wimbledon finale here at the All England Club two years ago.

The 30-year-old Serena, who's now a perfect 10-0 on grass this year, owns 14 major singles titles, including five Wimbledon championships, but still needs an Olympic gold medal to complete a career "Golden Slam."

Her quarterfinal opponent will be eighth-seeded former top-ranked Dane Caroline Wozniacki or capable Slovak Daniela Hantuchova.

The seventh-seeded Kerber, meanwhile, doused Venus in a pair of tiebreaks, 7-6 (7-5), 7-6 (7-5), as the veteran American had a bad serving day, as evidenced by seven double faults.

Kerber advanced in 1 hour, 49 minutes with the help of 36 unforced errors by Venus, and the German was a perfect 3-for-3 on break-point chances. Venus failed to convert on three set points in the opening stanza.

The 32-year-old three-time Olympic gold medalist Venus captured singles gold 12 years ago in Sydney and, like her fellow former No. 1 younger sister, is a five-time Wimbledon champ.

Also on Wednesday, sixth-seeded 2011 Wimbledon champ Petra Kvitova of the Czech Republic cruised into the quarters with a 6-3, 6-0 pasting of overmatched Italian Flavia Pennetta. The left-handed Kvitova will meet 14th- seeded Russian Maria Kirilenko in the round of eight. Kirilenko moved on with a 7-6 (7-5), 6-3 victory over German Julia Goerges.

And in a battle of former No. 1s, Belgian star Kim Clijsters upended 11th- seeded Serb Ana Ivanovic 6-3, 6-4. Clijsters is a four-time Grand Slam champ, while Ivanovic is a former French Open titlist.

In women's doubles action on Wednesday, a top-seeded American tandem of Liezel Huber and Lisa Raymond handled a sixth-seeded Russian duo of Ekaterina Makarova and Elena Vesnina 6-3, 6-3 to reach the semifinals. The 35-year-old Huber and 38-year-old Raymond are the reigning U.S. Open champs.