'This is crazy': Huge twist for Ash Barty in Australian Open chaos

Ash Barty will head into the Australian Open as the red-hot favourite as some of her biggest rivals continue to withdraw.

Three of the four women's semi-finalists from the 2021 Australian Open won't be back in 2022, with Serena Williams, Jennifer Brady and Karolina Muchova all out with injuries.

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World No.4 Karolina Pliskova and 2019 US Open champion Bianca Andreescu are also not making the trip to Australia.

On Tuesday it also emerged that World No.10 Ons Jabeur and Tokyo Olympics champion Bianca Bencic have tested positive for Covid-19, throwing their Australian Open participation in doubt.

Muchova, who beat Barty in the Australian Open quarter-finals this year, became the latest high-profile withdrawal on Tuesday.

“I’m sad to announce that my 2022 season will not start in Australia," the 25-year-old wrote on Twitter.

"I’m doing all I can to get back on the court as soon as I’m able."

The only semi-finalist left standing from the 2021 event is Naomi Osaka, who is scheduled to make her return to the WTA Tour in the lead-up to the Melbourne Park grand slam.

Osaka hasn't played since taking an indefinite break from tennis after the Tokyo Olympics, citing the need to protect her mental health.

Williams still hasn't recovered sufficiently enough from a leg injury suffered at Wimbledon, while Brady has pulled out because of a foot injury.

Pliskova, who lost to Barty in the Wimbledon final, will also miss the season-opening grand slam because of a right-hand injury sustained during a training session.

With the women's field decimated and question marks over a number of stars, the door is wide open for Barty to claim her maiden Australian Open crown.

Barty has never made it past the semi-finals at her home grand slam, while no local woman has won the Australian Open since Chris O'Neill in 1978.

Ons Jabeur and Belinda Bencic test positive for Covid

On Tuesday, Swiss star Bencic and Tunisia's Jabeur confirmed they had both tested positive following an exhibition event in Abu Dhabi, a day after Rafa Nadal revealed he had the virus.

Bencic, Jabuer and Nadal all travelled to the UAE capital to play in the Mubadala World Tennis Championship exhibition event last week.

Bencic lost to Jabeur in Abu Dhabi, who had replaced US Open champion Emma Raducanu after the Briton also tested positive for COVID-19 and withdrew.

Both Bencic and Jabeur said they were fully vaccinated and were experiencing strong symptoms.

"Unfortunately and even though I am fully vaccinated, I recently tested positive for COVID-19," Bencic said on Twitter.

However, Bencic was quietly confident of contesting the new year's opening slam which starts in Melbourne on January 17.

"I am currently isolating and taking all precautionary (measures) to get through this as best as possible as I am experiencing quite severe symptoms (fever, aches, chills)," Bencic posted.

"While the timing is not ideal - as I was in the final stages of my preparations for the Australian Open swing - I will make my way to Australia as soon as I am cleared and past the isolation period."

with AAP

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