Victoria Azarenka into 2nd round

— -- MELBOURNE, Australia -- Two-time champion Victoria Azarenka continued her comeback from a foot injury with a convincing 6-3, 6-2 win over Sloane Stephens on Tuesday and next will have to play US Open finalist Caroline Wozniacki, who beat 18-year-old Taylor Townsend 7-6 (1), 6-2.

No. 11 Dominika Cibulkova, a finalist here last year, opened with a 3-6, 6-3, 6-1 comeback win against Kirsten Flipkens.

Wimbledon champion Petra Kvitova needed only 63 minutes for her 6-1, 6-4 win over Richel Hogenkamp.

Limited to just nine tournaments last year, Azarenka's ranking has fallen to No. 44, and she is unseeded at a Grand Slam for the first time since the 2007 US Open.

Her Australian Open history with Stephens included the semifinals in 2013, when Azarenka controversially took an extended injury timeout at a critical point late in the match.

"Sloane is a very tricky opponent. It's a great first round for me to really test my game," Azarenka said. "I'm happy with what I did today."

Samantha Stosur opened with a 6-4, 6-1 victory against Monica Niculescu, and No. 19 Alize Cornet had a 6-3, 6-2 win over Zhang Shuai. No. 24 Garbine Muguruza and No. 25 Barbora Zahlavova Strycova advanced with straight sets wins, while Tsvetana Pironkova beat Hobart International champion  Heather Watson 6-4, 6-0.

The Associated Press contributed to this report.