Stephens races into Open round three as Bertens dumped

Melbourne (AFP) Former US Open champion Sloane Stephens powered into the Australian Open third round Wednesday as she strives to win a second major, but the tournament ended for ninth seed Kiki Bertens.

The American fifth seed swatted aside former doubles partner Timea Babos 6-3, 6-1 on Rod Laver Arena to keep her on a collision course to meet world number two Angelique Kerber in the quarter-finals.

Second seeded Kerber, the 2016 champion, resumes her tournament later Wednesday against fellow left-hander Beatriz Haddad Maia as she targets a 100th Grand Slam main draw win.

Six-time Melbourne winner Roger Federer is also in action, along with Rafael Nadal, defending women's champion Caroline Wozniacki and Russian starlet Maria Sharapova.

Stephens has endured a horror run at Melbourne Park since reaching the semi-final in 2013, exiting in the first round in 2015, 2016 and 2018.

She also missed 2017 with a foot injury, but looks to be back in business.

"Her serve is ridiculously good. I had to hang in there and be patient and I thought I did that well today," said Stephens, who next plays 31st seed Petra Martic.

Stephens and Babos have history. The two 25-year-olds played doubles in the junior ranks, and put together a 14-match winning streak in 2010 to capture the Roland Garros, Wimbledon and US Open doubles titles.

But powerful Dutchwoman Bertens, who raced through the rankings last year after winning three titles, failed to live up to expectations, crashing in three sets to Anastasia Pavlyuchenkova, who made the Melbourne quarters in 2017.

"I was maybe more a little lucky in the end, but she's a great tough opponent, she's top 10. That's a super great win for me," said the Russian.

Others safely into round three were 19th seeded Frenchwoman Caroline Garcia and Aliaksandra Sasnovich of Belarus, who upset Estonian 20th seed Anett Kontaveit.

- History not on side -

Swiss maestro Federer might be 37 but he's not feeling his age, with British qualifier Daniel Evans in his sights as he works towards a third successive Australian Open title and 21st major victory.

He defeated Evans at Wimbledon last year with the loss of just eight games, but remains wary.

"He's got all the shots. Likes to take chances, takes the ball early," he said of the 189th ranked player.

But history isn't on the Briton's side. The last time Federer lost to such a lowly ranked opponent was August 2000, when he was only 19.

The Swiss star's long-time rival and 17-time Grand Slam winner Nadal takes on local hope Matthew Ebden in a night match.

The Spaniard is bidding for his own slice of history by becoming the first man in the Open era, and only the third in history along with Emerson and Rod Laver, to win each Grand Slam on two or more occasions.

The NextGen charge is led by 14th seed Stefanos Tsitsipas and Sydney titlist Alex de Minaur, seeded 27, who are trying to reach the third round for the first time.

Tsitsipas faces a tricky test in Serbian Viktor Troicki while de Minaur, who has won eight of his nine matches this season, faces Henri Laaksonen.

Denmark's Wozniacki, who is battling rheumatoid arthritis, is bidding to become the first woman to defend the title since Victoria Azarenka in 2013.

She has a clash on Margaret Court Arena against Sweden's Johanna Larsson, while Sharapova is back in action after her 6-0, 6-0 "double bagel" opening round statement.

She also faces a Swede in Rebecca Peterson.