MELBOURNE, Australia — Sloane Stephens advanced at the Australian Open at the expense of her former doubles partner Timea Babos in a second-round match the women’s tour billed as a battle of the so-called “frenemies.”

Fifth-seeded Stephens, the 2017 U.S. Open champion, dominated the Rod Laver Arena opener 6-3, 6-1 on Wednesday but Babos kept her working by saving 18 of the 23 break points she faced.

The pair combined to win three junior Grand Slam doubles titles – the French, Wimbledon and U.S. Open – in 2010. Stephens said she knew what to expect from Babos but that didn’t make it any smoother.

“I just had to hang in there and be patient,” she said.

Stephens will next play No. 31-seeded Petra Martic, who beat Marketa Vondrousova 6-4, 7-5.

This is the first time since 2014 that Stephens has put back-to-back wins together at Melbourne Park. She reached the fourth round in 2014, a year after making a run to the semifinals.

“It’s tough getting back into the swing of things,” Stephens said of her preparation for the season-opening major, which this month included first- and second-round losses in Brisbane and Sydney. “It’s a little bit toasty, but a beautiful place to play.”

In other early women’s matches Wednesday, Anastasia Pavlyuchenkova eliminated ninth-seeded Kiki Bertens 3-6, 6-3, 6-3 to reach the third round of a major for the first time since her quarterfinal run here in 2017, and Aliaksandra Sasnovich beat 20th-seeded Anett Kontaveit 6-3, 6-3.

No. 19-seeded Caroline Garcia advanced 6-3, 6-3 over Zoe Hives 6-3, 6-3.

The brightest local hope for an Australian Open women’s title in decades is through to the third round as Ashleigh Barty beat Wang Yafan 6-2, 6-3 in a Rod Laver Arena match.

The 15th-seeded Barty was a finalist at last week’s Sydney International, beating No. 1-ranked Simona Halep along the way.

Halep pulled back from a set down to claim her opening match against 71st-ranked Estonian Kaia Kanepi on Tuesday, 6-7 (7-2), 6-4, 6-4.

On the men’s side, Stefanos Tsitsipas advanced to the third round and closer to a potential meeting with defending champion Roger Federer.

The Greek 20-year-old beat Viktor Troicki 6-3, 2-6, 6-2, 7-5 but wasted a lot of break-point opportunities as the Serbian player saved 15 of 19 chances created by Tsitsipas.

Considered one of the new breed of young talented players on the ATP Tour, Tsitsipas won at Stockholm last year and was a finalist in two other tournaments.

He will next play 19th-seeded Nikoloz Basilashvili, who beat Stefano Travaglie 6-3, 3-6, 6-3, 4-6, 6-3, also on Wednesday. Tsitsipas could play Federer in the fourth round.

Late Tuesday, top-ranked Novak Djokovic waltzed into the second round with a 6-3, 6-2, 6-2 victory over American qualifier Mitchell Krueger.