Ash Barty beat American Shelby Rogers 7-5 2-6 (10-4) in the quarter-finals of the Yarra Valley Classic ahead of the Australian Open.
The warmup events were suspended on Thursday as more than 500 players and officials were tested for COVID-19 after a worker at one of the quarantine hotels in Melbourne contracted the novel coronavirus.
World number one Barty and Rogers were among the first players out on court on Friday, playing under a closed roof at Margaret Court Arena on a rainy morning at Melbourne Park.
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"It was a tricky one, when the roof shuts here the conditions become quite sterile," said Barty.
"There were certainly some challenges today ... Happy to get through and get another opportunity tomorrow."
After being gifted the first set when Rogers crumbled on serve, top seed Barty was on the back foot in the second as the world number 60 found her range and began dominating the rallies with raw power.
Shelby's resurgence fizzled out in the tiebreak, however, and she surrendered the match with a wild backhand that sailed well past the baseline.
Faced with a scheduling logjam, the women's singles matches in the tune-up events have been shortened to two regular tiebreak sets with a 10-point super tiebreak if required for a final set.
Barty, who will carry Australia's hopes of a first home Grand Slam winner in 43 years, will meet either fifth seed Serena Williams or another American in Danielle Collins for a place in the final.
The Australian Open is live on Eurosport. Watch every match live and ad-free on the Eurosport app and You can download the Eurosport app for iOS and Android now.
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