LOUISVILLE, Ky. — Odanis Acuna, a veteran exercise rider for trainer Kenny McPeek, died early Saturday morning at Churchill Downs after suffering fatal injuries during training.

Daily Racing Form first reported that Acuna, 42, was breezing 2-year-old New York Harbor when the colt suddenly fell.

Onsite emergency medical technicians who arrived on the scene to treat Acuna believe he died instantly.

McPeek posted a statement on Twitter this morning, saying a GoFundMe page would be started soon for the rider's family.

"We are all sick and saddened by the loss of such a good man in Odanis Acuna," McPeek said. "We are working on all details to help his wife and children."

Acuna, nicknamed "Cuba" as a nod to his homeland, was said to have been a tireless worker dedicated to improving the life of his family.

“Odanis was one of the hardest working guys you’d ever meet; he was working the American dream,” said McPeek, who employed Acuna for nearly a decade. “He galloped for me in the morning and worked for the feed company in the afternoon.”

Sherry Stanley, Executive Director of the Backside Learning Center at Churchill Downs, said Acuna was working to bring his family to the United States.

“He was just a wonderful, wonderful person,” Stanley said. “His entire existence was focused on bringing his wife and three sons from Cuba to here in Kentucky. He was just about to finish the process of purchasing a home and the immigration paperwork to get them green cards."

This was first known training accident at Churchill Downs that resulted in the death of an exercise rider in several decades, according to veteran horsemen and track officials.

Training at Churchill was canceled for the rest of the morning. A moment of silence will be observed at approximately 12:30 p.m. in Acuna’s honor prior to Saturday’s first race at 1 p.m.

Funeral arrangements, a memorial service and fundraising efforts for the family are pending.

A GoFundMe has been put together for Acuna's family to help them in their time of need.