Two-time champion Victoria Azarenka has won her Australian Open first-round grudge match against Sloane Stephens, beating the American in straight sets at Melbourne Park for a third straight year.

Both players are unseeded for the first major of the year – with Azarenka having battled foot and knee injuries and personal issues in 2014, while Stephens suffered a slump in form.

But it was the Belarusian who dominated Tuesday’s encounter, winning 6-3 6-2 in 75 minutes.

In the pair’s first meeting two years ago, Stephens accused Azarenka of gamesmanship for taking a long medical timeout midway through their semi-final.

Last year, Stephens hit a forehand into Azarenka’s groin region during their fourth-round match, with the American’s attempts to apologise being ignored by the 2012 and 2013 Australian Open champion.

There were no further flashpoints on Tuesday, with Azarenka advancing to a second-round clash with No.8 seed Caroline Wozniacki or American Taylor Townsend.

Last year’s Open runner-up Dominika Cibulkova overcame a first-set blip to beat Belgian Kirsten Flipkens 3-6 6-3 6-1.

The Slovakian is seeded 11th, having enjoyed her best year on the tour in 2014.

Australian flagbearer Samantha Stosur, the No.20 seed, crushed Romania’s Monica Niculescu 6-4 6-1.

No.24 seed Garbine Muguruza from Spain beat New Zealand’s Marina Erakovic 7-5 6-0.