Horse racing is among America’s oldest sports and perhaps the only one ever run out of the White House: Andrew Jackson operated a stable there during his presidency. Yet the multibillion-dollar industry is reeling as the Kentucky Derby approaches, with the death of yet another thoroughbred at the premier Santa Anita Park in California amplifying anxiety over whether the sport will continue in the state.

On Sunday, a gelding named Arms Runner fell during a race, sustaining a catastrophic injury to its right front leg that required the horse to be euthanized. It was the 23rd equine fatality since Dec. 26, and it came on only the third day of racing at the track since it had halted competition on March 5.

“I’m concerned about the publicity we’ve been getting,” said Bob Baffert, the Hall of Fame trainer who won the Triple Crown with American Pharoah in 2015 and with Justify last year. “This is our March Madness. But we’re having the wrong kind of madness. We feel like we’re all under the gun. We should be under the gun. You can’t defend a horse getting hurt.”

The track, in Arcadia, Calif., northeast of Los Angeles, had been closed to study why it had become so deadly, as well as to begin putting in place aggressive, wide-ranging drug and safety protocols. The spike was startling considering that in 2017, there were 20 deaths in a total of 8,463 starts over a span of 122 racing days at Santa Anita, according to Jockey Club data.