Tasmania's outstanding filly Still A Star has been scratched from Saturday's $150,000 Tasmanian Derby in Hobart after blood tests revealed she had a high white cell count.
This can be indicative of a minor cold or virus.
The elevated reading showed up in a blood test taken early in the week but connections only learned of the result on Thursday.
A further test was taken on Friday morning and revealed the white cell count was almost back to normal but Longford trainer Bill Ryan, after consulting the filly's owners, decided not to risk running her in the Derby where she had been the $1.50 favourite.
All being well, she will now tackle the $100,000 Strutt Stakes against her own sex in Hobart on Sunday week.
Still A Star has won five of her 10 starts and finished second in the other five races.
She has beaten the males in the $100,000 Tasmanian Guineas and $100,000 Launceston Guineas at her past two starts.
Victorian visitor Rogues Point, trained by Anthony Freedman and a late pick-up ride for Craig Newitt, is now favourite for the Derby at $1.50.