When 21-year-old Australian Ashleigh Barty stepped into Rod Laver arena for her first round Australian Open clash against 19-year-old Belarusian Aryna Sabalenka, she knew what to expect.

She knew her opponent, ranked world number 66, had a history of screaming, or grunting, after every shot she hit. And she knew it would be distracting.

But as prepared as she was, Barty admitted after the match – which she won 6-7 6-4 6-4 – that her opponent’s sounds were louder than she expected.

“I knew it was coming but it was a bit louder than I thought,” she told reporters after the clash.

“But I knew I had to let that go and just concentrate on myself.

"A lot of players grunt. A lot of players don't grunt. It's just the way they are, the way they play. For me, it wasn't a distraction. It wasn't anything like that. It was just part and parcel."

But even if the world number 17 wasn't phased by her opponents sounds, the crowd certainly was: the central umpire was forced to plead with the crowd after they started imitating the squeals late in the second set.

"Ladies and gentlemen, please, during the rally, do not scream," she said, which only prompted more sounds from the crowd.

"Please. Out of the courtesy for the players..."

Tennis greats were also among those watching the match who criticised Sabalenka's tactics.

Nice player #Sabalenka but something needs to b done about her noise and grunting on court!!!! @WTA change channel #watchsomethingelse

— Todd Woodbridge (@toddwoodbridge) January 16, 2018

Other viewers also shared their thoughts about the noise on Twitter, with some even branding it as a form of "cheating".

Shrieking is nothing new but I’m not sure why umpires/officials don’t call players out on it. Hard to watch. Sabalenka’s needlessly loud and extended moaning is deliberate verbal intimidation

— Nick Wade (@nick_wade) January 16, 2018

Cheating from Sabalenka with the noise. Distracting. Shouldn’t be allowed. Often forcing it out seconds after playing the shot#AusOpen

— Jack (@jblr_95) January 16, 2018

Cannot believe a player is allowed to make such a God awful noise when playing as Sabalenka does. Should be a rule against this blight on the game. Unbearable. #AustralianOpen Go @ashbar96 !

— Rich Gregory (@gegsy1) January 16, 2018

Ok now I’m 100% positive she’s grunting/making noise after hitting the ball and it’s puzzling how Sabalenka is not getting called for hinderance #AusOpen

— Adam (@adam_63) January 16, 2018

Aryna Sabalenka's grunt #AusOpen pic.twitter.com/CTi1iZikP7

— Tennis Memes (@ATPWTAMemes) January 16, 2018

Of course, 'grunting' in tennis is nothing new, and the likes of Monica Seles, Serena and Venus Williams, Maria Sharapova, Rafael Nadal, and Novak Djokovic are all known to make a bit of noise on the court.

Players have, in the past, called for a ban to be placed on the noise. Ivan Lendl complained about his opponent Andre Agassi's grunting during the 1988 US Open, saying it "threw off the timing" of his return shots.

LISTEN: As soon as she picked up a tennis racket, Jelena Dokic started being abused by her father...

In 2009, former tennis great Martina Navratilova described the practice as a form of cheating, saying that not only was the noise distracting to other players, but that it drowned out the sound of the ball leaving the racquet.

This, in turn, prevented a player from using the sound to determine their return stroke.

Other players, like Maria Sharapova, have said they've grunted ever since they started playing and "weren't going to change".

Serena Williams has said she is "not conscious" of when her physical exertion turns verbal in a match.

"I'm just zoned out," she said.

For now, Ashleigh Barty is putting the drama of her first 2018 Australian Open match behind her, as she gets ready to face world number 17 Italian Camila Giorgi in the second round of the tournament.

LISTEN to Mia Freedman's full interview with Jelena Dokic on No Filter: