The four-year-old had featured prominently for a long way in the showpiece event that brought the two-day meeting to a close, but was taken off the track in a horse ambulance after suffering a serious leg injury in the straight.
Following further examination and observation at the equine hospital at Santa Anita, it was announced the Enebish Ganbat-trained gelding had been humanely euthanised.
The fixture had been under intense scrutiny following a sharp rise in equine fatalities at the California track earlier in the year.
A statement from the Breeders’ Cup read: “Mongolian Groom sustained an injury in the Breeders’ Cup Classic today and was immediately attended to by an expert team of veterinarians, led by board certified veterinary surgeon Dr Ryan Carpenter.
“During their evaluation at the equine hospital at Santa Anita, they observed a serious fracture to his left hind limb. Radiographs were taken and a complete evaluation was performed.
“Given the extent of the injury, Dr Carpenter, in consultation with Dr Wayne McIlwraith, veterinary surgeon and professor emeritus at Colorado State University, Dr Rick Arthur, Equine Medical Director of the California Horse Racing Board, and attending veterinarian Dr Vince Baker, recommended humane euthanasia of Mongolian Groom.
“The death of Mongolian Groom is a loss to the entire horse racing community. Our equine and human athletes’ safety is the Breeders’ Cup’s top priority. We have worked closely with Santa Anita leading up to the World Championships to promote enhanced equine safety.
“Santa Anita has implemented numerous industry-leading reforms to enhance the existing health and safety measures with the intent of providing a safe racing environment.
“In addition, Breeders’ Cup always observes the most thorough up-to-date medication practices and restrictions, testing protocols, equine security and surveillance program, veterinary exams, injury management protocols and racing surface testing.
“These measures are in place to ensure our athletes are racing under the safest and most transparent conditions possible.
“Breeders’ Cup has engaged world-renowned veterinarian, Dr Larry Bramlage, to conduct an independent evaluation, the results of which will be published when completed.
“We will continue to keep all stakeholders apprised as information becomes available. We are committed to working with our partners in the industry to continue to advance safety reforms, with the well-being of our athletes in mind.”
The race was won by Vino Rosso, beating the Bob Baffert-trained favourite McKinzie.
Baffert told nbcsports.com: “Such a shame. We put on such a good show for almost two days, and then we got so close to the finish in that last race. I feel terrible for the connections of that horse. I feel bad for the whole sport.
“It’s just really sad. I don’t know what else to say.”
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