Caulfield and Melbourne Cup contender Cedarberg has collapsed and died after a routine trackwork gallop on Tuesday morning at Moonee Valley.
The BMW winner dropped dead after completing a 1600m hitout.
Trainer Pat Carey said it was too soon to confirm reports the stayer had suffered a heart attack.
“From what I would think, usually it would be something like a ruptured aorta but the horse will have a post-mortem on him and time will tell,” he told a Sydney radio station.
Cedarberg collapsed and fell through the running rail between the 1400m and 1500m.
His jockey Rhys McLeod was not hurt.
Cedarberg was a lightly-raced stayer who entered the spring picture with a breakthrough Group I win in the weight-for-age BMW at Rosehill on Golden Slipper day.
The five-year-old resumed over an unsuitable distance and pleased Carey with his midfield placing in the Aurie’s Star Handicap at Flemington on August 6.
A $26 chance to win the Caulfield Cup and rated a $51 hope for the Melbourne Cup, Cedarberg was nominated to continue his run towards both races in a Moonee Valley event on Saturday.
“He was well positioned for the spring … the horse looked quite forward in himself and looked in fantastic health,” Carey said.
“We felt we were in a pretty good place to go forward.”
Besides his BMW triumph, Cedarberg won another three races and banked more than $1.5 million in stakes
by Buford Balony