Practical Move, the Santa Anita Derby winner who was considered a favorite for the Kentucky Derby before scratching out with a fever, dropped dead of an apparent cardiac event after finishing a morning gallop at Santa Anita on Tuesday, according to the Breeders’ Cup.

His rider was not hurt and the horse was immediately attended to by veterinarians, but they were unable to save him. Using defibrillators, commonly used on humans after a cardiac event, is not feasible on horses because the amount of voltage needed for a 1,000-pound-plus animal would put the person administering it at serious risk.

In addition, Arcangelo, who made Jena Antonucci the first woman trainer to win a Triple Crown race after winning the Belmont Stakes, pulled out the Classic and was retired. The news was first reported by Joaquin Jaime of FanDuel TV. The Daily Racing Form reported that Arcangelo will be retired and stand next year at Lane’s End Farm.

“From day one, we will always be horse first, no matter what, Antonucci said.

The horse has been dealing with a hind hoof issue since the weekend.

Arcangelo was the only Triple Crown winner scheduled to run in the Classic. Mage dropped out this week after developing a fever. National Tresure, winner of the Preakness Stakes, is scheduled to run in the Dirt Mile, the same race as Practical Move. The favorite will be Cody’s Wish.

On Saturday, Geaux Rocket Ride suffered a serious injury that ended his racing career. He underwent surgery on Sunday and the owners said that the recovery has been difficult. The 3-year-old colt is fighting for his life.

Earlier, Echo Zulu, the 2021 Eclipse winner of 2-year-old filly, also suffered an injury while training for the Breeders’ Cup but her recovery is progressing as scheduled.

The Breeders Cup will be held Friday and Saturday at Santa Anita.