Former Australian Open champions Naomi Osaka and Victoria Azarenka have both pulled out of their respective WTA warm-up events.
World No.3 Osaka withdrew from her Gippsland Trophy semi-final against Elise Mertens on Saturday, citing the need to manage a niggling injury ahead of her Open campaign.
"Sorry to Tennis Australia and the fans to have to withdraw today," Osaka said.
"I have a niggling injury and in light of the AO on the horizon, I need to be cautious.
"I look forward to competing next week."
Osaka will face Russian Anastasia Pavlyuchenkova in the first round.
As a result, Mertens has a walkover to the final of the Gippsland Trophy.
Shortly after Osaka's announcement, the WTA tweeted Azarenka had withdrawn from her Grampians Trophy quarter-final clash with Anett Kontaveit with a lower back injury.
Azarenka, who was one of the players forced into a hard 14-day hotel quarantine, is scheduled to face American Jessica Pegula in the first round.
Consequently, Kontaveit progresses to the Grampians Trophy semi-finals.
