Ash Barty has pulled out of the women's doubles as an abdominal strain threatens her Australian Open campaign.
The world number 15 was in dominant form during her third round win over Maria Sakkari on Friday, but needed medical treatment midway through the match.
Speaking after the 7-5 6-1 victory, Barty played down the injury, describing it as a minor abdominal strain.
It's been a busy couple of weeks for Barty, having played the Hopman Cup earlier in the year and making the final in Sydney just two days before the Australian Open started.
MORE: Barty waltzes into maiden Aus Open fourth round | Serena's beautiful moment with Yastremska
With a fourth round match opposite Maria Sharapova on Sunday, Barty wasn't taking any risks, and decided to pull out of the doubles event.
"I think I have just gotten to know my body well enough now to know when I need a little bit of help," she said after her medical timeout against Sakkari.
"It was more just for a bit of reassurance and support. I knew it wouldn't affect me on court. It was more just a reinsurance."
She had been playing alongside Victoria Azarenka, and had been scheduled to take on American duo Jennifer Brady and Alison Riske in the round of 32 on Saturday.
Barty and former Australian Open champion Azarenka earned a hard-fought 7-5 4-6 7-5 win over Peng Shuai and Yang Zhaoxuan on Thursday.
After beating world number one Simona Halep and 2017 French Open champion Jelena Ostapenko, Barty took two-time Wimbledon champion Petra Kvitova to three sets in the final in Sydney.
In Melbourne, Barty made light work of Luksika Kumkhum, Wang Yafan and Sakkari but will face a tough challenge against Sharapova on Sunday.
"It's another opportunity for me to go out and test myself against the world's best," she said.
"It's getting to the point now where I'm feeling more and more comfortable on the court and can play my brand of tennis, which when I execute I know it works against the best in the world."