One horse suffered a catastrophic injury and two more horses went down, losing their riders, in the seventh race Thursday at Fair Grounds.

Jim’s Silverbullet, ridden by Marcelino Pedroza, broke down in the homestretch of a $15,000 maiden-claiming dirt race, and in avoiding the stricken horse Robby Albarado on Awe Patriot and Mitchell Murrill on Max Pandowdy were unseated. Albarado walked off the track and Murrill, after being transported from the course by ambulance, didn’t require further medical treatment. His agent, Tim Hanisch, said Murrill had a sore back and hoped to ride Friday.

Pedroza was transported to a nearby hospital, according to Fair Grounds stewards. His agent, Richie Price, didn’t immediately respond to texts or calls regarding Pedroza’s condition. There was no indication Pedroza had suffered anything worse than a fracture.

Jim’s Silverbullet was vanned off the course had to be euthanized because of severe injury, according to Fair Grounds stewards. Awe Patriot and Max Pandowdy both crossed the finish rider-less and appeared to have avoided serious injury.

Earlier Thursday, in race 4, Star Yankee was pulled up and vanned off after running in a dirt race. Three horses were vanned off the dirt track during racing last Thursday, Jan. 9, including J Rob, who suffered a displaced condylar fracture and had to be euthanized. In the seventh race on Jan. 11, Big Shanty broke down badly in the stretch run of a dirt race.