ASHLEIGH Barty has the day off today. And she'll need it to clear out her ears after Aryna Sabalenka's noise-filled performance on Tuesday night.

The 19-year-old earned the wrath of fans and commentators alike for her grunting, shrieking and screeching in what was otherwise a highly-entertaining three-set clash with the plucky Aussie.

Australian tennis great John Newcombe once referred to grunting - then in relation to former world No. 1 Maria Sharapova - as "legalised cheating".

And head of Australia's women's tennis Nicole Pratt agrees.

"It is," she said on 3AW.

"The player does rely on the sound of the ball coming off the racket.

"And probably more the issue is when players grunt or scream for an extended period of time because then that is impeding on your hitting time and hitting space.

"There is a bit of an issue when it does get extended."

After a big day for the locals on Monday, Barty was the only Aussie winner on Tuesday.

Day three features Aussies Nick Kyrgios, Matthew Ebden, John Millman, Olivia Rogowska and Daria Gavrilova.

Kyrgios faces Serbia's Viktor Troicki; Ebden looks to follow up his first-round upset of John Isner against Alexander Dolgopolov, Millman plays 28th seed Damir Dzumhur while Rogowska plays Ukraine's Marta Kostyuk and Gavrilova faces young Belgian Elise Mertens.

Caroline Wozniacki, Jelena Ostapenko, Elina Svitolina, Grigor Dimitrov and Rafael Nadal are all playing as well.

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