Doctors will transfer Jockey Edward Creighton to a Melbourne hospital following a fall at Warrnambool on Saturday.
Victorian Jockeys' Association chief executive Des O'Keeffe said Creighton had a seizure while being assessed at the Warrnambool Base Hospital.
He said Creighton was being transferred to undergo more scans.
Creighton suffered a suspected broken left arm in the fall and was conscious after the incident.
The jockey fell from first starter The Walrus in the opening race.