The past two Golden Slipper winners could both be missing from the spring carnival.
Estijaab, winner of the 2018 Slipper, is having an extended break while last year's winner She Will Reign is being monitored after she was found to have blood in one nostril.
Trainer Gary Portelli has told stewards the results of a lung wash performed on She Will Reign will be known later on Tuesday and will tell whether the blood was the result of external trauma.
She Will Reign will need to gallop satisfactorily before stewards and require a veterinary clearance before she races again.
The mare, who has been sold to an undisclosed buyer, finished sixth in her return in the Missile Stakes last Saturday week.
The spring carnival is scheduled to be her final campaign for Portelli and Darby Racing.
Trainer John Hawkes has told stewards Estijaab will not race during the spring.