World number one Ash Barty withdrew from the Australian Open doubles on Friday, raising concerns over her fitness for the singles as she manages a thigh strain.
Barty played with her left thigh heavily strapped in her second round win over fellow Australian Daria Gavrilova but downplayed the injury on Thursday, saying she was "fit as a fiddle."
She and American Jennifer Brady were scheduled to play in the second round of the women's doubles on Friday but withdrew from the match, handing Elise Mertens and Aryna Sabalenka a walkover.
Top seed Barty, who made the semi-finals last year, is bidding to end Australia's 43-year wait for a home winner at the Grand Slam.
(Reporting by Ian Ransom; editing by Richard Pullin)
