The French galloper Trevieres has fractured a canon bone during trackwork at Werribee on Monday, ruling him out for the spring.
Trevieres had completed his morning exercise, cantering for 1200m at Werribee racecourse where he's been stabled for the past three weeks.
As he walked back to the quarantine barn his handler Stephanie Nigge slipped out of the saddle when she noticed the horse had become lame as he cooled down.
The damage was later revealed in a scan.
Trevieres created a big impression in his only Australian start when second in the Group One Toorak Handicap at Caulfield earlier this month.
His Australian connections had been tossing up whether to run next in Saturday's Mackinnon Stakes or the Emirates Stakes at Flemington a week later.