'Didn't feel right': Australian Open champ's hidden health battle

Reigning champion Sofia Kenin's premature exit from the Australian Open was surprising enough - let alone her subsequent first-round loss at the WTA's Phillip Island Trophy days later.

It was a confusing run of form from the world No.4, who hadn't reported any dramas or concerns while quarantining in Melbourne ahead of the year's first grand slam - but the 22-year-old has since shared a possible reason for her surprisingly poor form.

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Kenin revealed on Twitter that she had been taken to hospital to have surgery for appendicitis earlier this week, just a day after her first-round Phillip Island Trophy loss to unranked Australian teenager Olivia Gadecki.

The American star was bounced out of the Australian Open's second round after a straight sets loss to world No.65 Kaia Kanepi.

Sharing the news on Twitter, Kenin said she had made a full recovery after having a procedure at Melbourne's Epworth Hospital.

"Hey guys! I want to share with you what happened to me a few days ago," Kenin wrote.

"I went to the tournament physician office on Monday, February 15th with acute abdominal pain. I was evaluated by the tournament physician and referred to the hospital for further evaluation.

"Acute appendicitis was diagnosed following the completion of my CT scan.

"I had to have surgery and had my appendix removed on Monday, February 15, at Epworth Hospital Richmond. I want to thank everyone at Epworth Hospital Richmond for taking good care of me!"

There were plenty of fans on social media who were relieved to hear Kenin was recovering well, as well as other fans who were pleased there was some explanation for her uncharacteristically poor form.

Ash Barty's Australian Open run over after upset

Czech Barty-pooper Karolina Muchova has ensured that the wait for a home-grown Australian Open champion will extend to 44 long years.

Only two days ago, world No.1 Ash Barty warned anyone who cared to listen that her quarter-final opponent was "a hell of a player".

After a sluggish start and a strategic medical time-out early in the second set, Muchova lived up to that billing on Wednesday, ousting Barty 1-6 6-3 6-2 to advance to an unlikely semi-final showdown with American Jennifer Brady.

"I think it was bit of the heat and it got to me," said the 24-year-old Muchova, who hails from the scenic eastern Czech city of Olomouc.

"I was feeling kind of dizzy at some point, really lost and almost fainting.

"So, yeah, I just asked for help.

"Definitely they cooled me down with the ice.

"The doctor checked my pressure, my temperature and everything."

Whatever it was the medical staff did, it worked.

The 25th-seeded Muchova could barely miss when the match resumed, while an increasingly flummoxed Barty racked up the unforced errors.

"I'm just trying to be really calm, to not think about previous mistakes and all of it," said Muchova, whose other scalps at Melbourne Park this year include countrywoman and former world No.1 Karolina Pliskova and No.18 seed Elise Mertens.

With AAP

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