Medina Spirit, the Thoroughbred who won the 2021 Kentucky Derby under suspicious circumstances, has died according to Dr. Jeff Blea, the California Horse Racing Board’s equine medical director.

The 3-year-old racehorse collapsed after a workout at Santa Anita Park on Monday morning during which he completed five furlongs. It was his second workout since finishing second in the Breeders’ Cup Classic.

“I spoke to the attending veterinarian, and when they got to him on the track, he had already expired,” Blea told the Paulick Report. “He’ll go out to UC Davis in San Bernardino for a full and comprehensive necropsy including toxicology, forensics and tissue sampling. We will take a close look at the heart to try and identify the cause of death.”

Medina Spirit’s Kentucky Derby win had been in jeopardy after he tested positive, postrace, for betamethasone — a therapeutic drug banned from use on race day. The Kentucky Horse Racing Commission had not held a hearing related to the case.

Baffert said that the Thoroughbred turned up a positive test for a corticosteroid because of an ointment used to treat a skin rash. On Friday, Baffert’s attorneys released a statement saying that a New York lab had confirmed this assertion.

In addition to the Breeders’ Cup, Medina Spirit raced in the Preakness Stakes, finishing third, and won two other races. In 10 starts, the colt had five wins and earned more than $3.5 million.

Owned by Saudi Arabian businessman Amr Zedan, Medina Spirit was training to possibly compete at the Saudi Cup in February.