Victoria Azarenka was an easy winner Wednesday in the second round of the season-opening Brisbane International.

The top seed and world No. 1 opened her 2013 campaign with a 6-3, 6-3 victory over German Sabine Lisicki. Azarenka, who won this event in 2009, had a bye into the second round as she begins preparations to defend her Australian Open title.

It was a banner 2012 for Azarenka, who added five other WTA titles to her first Grand Slam championship. She also won the Aussie Open tune-up in Sydney, as well as tournaments in Doha, Indian Wells, Beijing and Linz, while finishing as a runner-up three times -- the last coming at the U.S. Open.

Next up for the Belarus star will be Kazakhstan's Ksenia Pervak, who had advanced to the quarterfinals on Tuesday with a three-set win over Urszula Radwanska. Pervak, who first had to qualify for the main draw, also upset former world No. 1 Caroline Wozniacki in the first round earlier this week.

Germany's Angelique Kerber, American Sloane Stephens and Ukrainian lucky loser Lesia Tsurenko were the other second-round winners Wednesday.

Kerber rallied for a 3-6, 6-4, 7-6 (9-7) victory over Puerto Rican qualifier Monica Puig. The fourth seed struggled throughout on Wednesday, but was able to come back from deficits of 1-4 in the third set and 2-5 in the ensuing tiebreaker to advance to a quarterfinal match against Russian Anastasia Pavlyuchenkova.

Stephens had little trouble in a 6-3, 6-4 triumph over Sweden's Sofia Arvidsson, who had knocked off Aussie favorite Samantha Stosur in the first round. Next up for the 19-year-old Stephens will be fellow American Serena Williams, who has yet to be tested in her first two matches of the year.

Williams, the third seed, has dropped just seven games in her first two matches this week and will carry a 14-match winning streak into Thursday's quarterfinal.

Tsurenko was given entry into the main draw after second-seeded Maria Sharapova pulled out of the tournament because of a collarbone injury and took full advantage with a 1-6, 6-1, 6-4 victory over Australian wild card Jarmila Gajdosova. She'll next play Slovakian veteran Daniela Hantuchova, last year's runner-up, in Thursday's quarterfinals.