The inaugural running of the Dubai Gold Cup was halted after Fox Hunt broke down and fell during the early stages of the two-mile race at Meydan.
Jockey Silvestre de Sousa appeared to escape unscathed in the fall but the Godolphin-owned five-year-old lay stricken on the ground.
The race was stopped as the runners went down the back straight and the jockeys quickly pulled up their mounts.
Fox Hunt broke a leg after appearing to clip heels with just over a circuit to run and was put down.
Frankie Dettori, who was on Fox Hunt's stablemate Opinion Poll, said: "The horse just broke his leg. Unfortunately he fell right at the point on the corner rounding the home turn, so we weren't aware where the horse was.
"The officials came alongside us at halfway and told us to stop the race, they did the right thing.
"If we had carried on and tried to avoid a dead horse there could have been more casualties."
Richard Hills, who was riding Zanzamar, said: "I was right behind him. He went straight down. I don't know whether he clipped heels or the leg just broke.
"The guy upsides with the camera shouted to us the race was off."
De Sousa said: "I'm feeling fine, it was just a bit of a shock. He was aways doing a bit too much on the bridle and was galloping on the wrong leg. They did the right thing (to stop the race)."
The race was re-run after the Durbai World Cup and Opinion Poll gave Godolphin a treble on the night.
The rescheduled contest, run a little over four and a half hours later, was not without incident as both Bronze Cannon and Grand Vent were pulled up.
Frankie Dettori was following up his win on African Story in the Godolphin Mile as he enjoyed a cosy success on Opinion Poll.
He kicked on early in the straight on the Mahmood Al Zarooni-trained hot favourite and had enough in hand to hold the late challenges of Joshua Tree and Zanzamar, with the latter the final ride of the retiring Richard Hills.
