Jockey Brian Toomey was on Thursday night suffering from a "life-threatening head injury" in hospital following a heavy fall at Perth.
Toomey, a 3lb claimer, was partnering the Lisa Harrison-trained Solway Dandy in the Book Now For 2014 Perth Festival Conditional Jockeys' Handicap Hurdle when the 11-4 favourite came to grief three flights from home.
An air ambulance arrived shortly after the accident, but Toomey was instead transported to Dundee's Ninewells Hospital by road.
Speaking shortly before 10pm, a spokesperson for NHS Tayside said Toomey was "suffering from a life-threatening head injury."
Toomey is attached to the yard of Kevin Ryan in North Yorkshire and is the boyfriend of the trainer's daughter, Amy.
Hambleton Racing have horses with Ryan and tweeted: "Very concerned to hear the news about Brian Toomey this evening, thoughts with him and Amy."