Former US Open champion Bianca Andreescu is out of the Grampians Trophy WTA 500 event.
Andreescu was the top seed for the tournament, which was arranged for players who were forced into hard quarantine after arriving in Australia.
She had a scheduled bye in the first round but is now out of the draw and won't have tournament matches before the Australian Open.
The World No.8 said the withdrawal was a precautionary measure after she spent 14 days in quarantine upon arriving in Australia.
"Following the last two weeks in quarantine, it feels so good to finally be back on the court. After discussing it with my team, we have decided to focus this week on training for the Australian Open and miss the Grampians. Many thanks to Tennis Australia and the WTA for their hard work in providing us all of these choices. See you all at the Australian Open!" Andreescu said in a statement.
The 20-year-old Andreescu, ranked eighth in the world, would have faced the winner of a match between fellow Canadian Leylah Annie Fernandez and American Sloane Stephens in the second round.
Bianca Andreescu with the US Open trophy after beating Serena Williams.
The Grampians tournament was organised for players coming out of hard quarantine following COVID-19 exposure on charter flights to Australia.
Andreescu hasn't played since October 2019 after suffering a left knee injury at the WTA Finals.
After beating Serena Williams in the final at Flushing Meadows that year, she spent the whole 2020 season on the sidelines.