Ashleigh Barty felt she lost control of her Australian Open quarter-final before losing in three-sets to Karolina Muchova.

It's a cruel irony that the last remaining home favourite in Melbourne was forced to depart just ahead of the fans' return after a snap lockdown.

Barty had opened the tournament with a 6-0, 6-0 win, and looked set to breeze into the semi-finals in a similar fashion when she took the first set from Muchova 6-1.

"I felt like I was in control of the match", the top seed said afterwards.

Trailing 1-6 and 1-2 in the second, Muchova took a 10-minute medical time-out after complaining of dizziness.

From that point, the match turned on its head.

Barty produced 30 unforced errors following that break in play, compared to seven in the ten games that had preceded it.

"I'm just disappointed with the fact that I wasn't able to bring the match back on my terms after she took that break," Barty said.

"I felt like I had small windows of opportunity probably midway through the second set and wasn't able to regroup enough to be clear in the third set how I wanted to play.

"I've played a lot of matches where there have been medical timeouts. I've taken medical timeouts myself before, so that shouldn't be a massive turning point in the match.

"I was disappointed that I let that become a turning point. I'm experienced enough now to be able to deal with that.”

From desktop to real life

For Muchova, the win sees a long-held dream manifest itself into reality.

"I actually have one memory from here when I was a kid and got my first notebook computer," the Czech said after the match.

"I put as a wallpaper Rod Laver, the stadium. I was just, like, I hope one day, it would be nice to play there, or to look at the arena.

"Now, yeah, I just won a match and make it to semi-finals. It's amazing."

Muchova felt accomplishing the win over Barty was "tough", adding, "It was the first time in this position, so I just tried not to think about it, and only like it was just another ball.

"I’m happy with how I handled it."

Waiting for Muchova in the semi-finals is the 22nd seed, Jennifer Brady.

She too had to come from a set down before beating her fellow American Jessica Pegula in three sets.

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