On Saturday night at the Australian Open, Ashleigh Barty will stand on the brink of her biggest achievement in tennis – reaching the fourth round of a major.

The 21-year-old’s rise through the sport has been incredible to watch, and all the more given her two-year hiatus in 2015 and 2016.

Beginning the world ranked outside the top 150, Barty defeated grand slam winners Garbine Muguruza, Venus Williams, Angelique Kerber, Jelena Ostapenko and others to surge into the sport’s top 20 players.

She made finals in Kuala Lumpur, Birmingham and Wuhan, and more recently Sydney, and was crowned John Newcombe Medallist.

But she’s yet to reach the second week of a grand slam, a prize that awaits her if she can overcome fellow up-and-comer Naomi Osaka.

“It would be amazing. It really would,” she said.

Osaka is the third-straight heavy-hitter in Barty’s path.

The world No.72 follows Belarusian teen Aryna Sabalenka and in-form Italian Camila Giorgi, both of whom won the first set against Barty.

Australia’s last remaining woman at Melbourne Park said: “Naomi is a great chick and can certainly give the ball a rip when she’s got time.

“I think for me it’s sort of not overly usual to have three matches very similar.

“I’m very excited to be in the third round again, put myself in a position where I can go deeper in the tournament.

“I’ve been able to hang around long enough in these matches (so) I can go out there on Saturday, have a red hot crack and try to make my first fourth round.”

Barty is the only Australian in singles action on Saturday, and will close the day session on Rod Laver Arena.

Top seed Simona Halep and Lauren Davis will battle in the opening match, with the winners of those two clashes to meet in the fourth round.

The most anticipated match-up of the day is between 2016 champion Angelique Kerber and 2008 winner Maria Sharapova, to begin at 7pm.

Revered Swiss great and defending champion Roger Federer closes proceedings against Richard Gasquet on Melbourne Park’s centre court.