World number one Victoria Azarenka opened her 2013 season with a 6-3 6-3 win over Germany's Sabine Lisicki in Australia on Wednesday.
Azarenka joins world number three Serena Williams and fourth-seeded Angelique Kerber in the Brisbane International quarter-finals that take place on Thursday.
The 23-year-old won her first major at the Australian Open last year during a 26-match winning streak to start the season.
Earlier, Kerber fought back from 5-2 down in the deciding tiebreaker to beat Puerto Rican qualifier Monica Puig, 3-6 6-4 7-6 (7-5) in her second-round match.
Sloane Stephens had a 6-3, 6-4 win over Sweden's Sofia Arvidsson to set up a quarter-final against fellow American Williams.
Azarenka said Lisicki, proved a tough match and the game was a good measure of her preparations for the Australian Open, which starts on January 14.
"I had a tough challenge at the beginning," she said. "It's always good to see where you're at, right at the start."
She will next play Kazakh qualifier Ksenia Pervak, who has ousted former world number one Caroline Wozniacki and Urszula Radwanska in matches decided by third-set tiebreakers.
Azarenka added: "I hope she's tired. She's a young girl with a lot of potential. She's going to be really motivated. I'm looking forward to the challenge."