Charlie Appleby and William Buick pulled off one of the most dramatic victories in Breeders’ Cup history at Del Mar in the early hours of Saturday after Modern Games won the Juvenile Turf, having been ruled out of the $1 million feature just minutes earlier.

There was drama and confusion at the start of the mile contest when Albahr, also trained by Appleby and drawn next to his stablemate, became restless in the stalls. He fell backwards and kicked out before being led away with a few superficial cuts.

A shaken Frankie Dettori, the jockey of Albahr, said his mount had “freaked out” and was indebted to stalls handlers for freeing him. One of them limped away and required medical attention.

Race officials immediately scratched Albahr and moments later it was announced that Modern Games would also be a non-runner after he came out of the front of the stalls. As in England, that usually means non-participation in the race but in this instance there were mitigating circumstancxes with the gate deliberately being opened to allow Modern Games quickest escape to the events unfolding next to him.

Vets at the scene announced they were happy for the favourite to take part.

It still took several minutes to confirm he could line-up, though, because by now the colt had been taken out of American betting pools and no longer existed in terms of wagering on the contest. Rules dictated he could run for purse money, but that all bets on him would be void.

Appleby watched on in despair, believing that the 11,000-round mile trip for his two Godolphin contenders would be fruitless. He described the episode as "surreal".

The race itself, having been delayed more than 15 minutes, was remarkably straightforward with Buick and Modern Games sweeping through from off the pace to win in fluent fashion from Tiz The Bomb and Mackinnon.

As a consequence, we had the unprecedented event of a Breeders’ Cup winner returning in triumph without a starting price, and without anyone betting into the American pool having benefitted from his victory. Some racegoers, who had no doubt placed bets on him, vented their frustration with boos.

Breeders’ Cup races are subject to California Horse Racing Board (CHRB) rules, including one which states: “If a horse is removed from the wagering pool due to a totalizator error, or due to any other error, and neither the trainer nor the owner is at fault, the horse shall start in the race as a non-wagering interest for the purse only and shall be disregarded for pari-mutuel purposes.”

Afterwards, the CHRB and Breeders' Cup said it would review procedures "to ensure that this "does not occur going forward". A statement issued by Breeders' Cup read: "We thank the CHRB for their thorough review of this situation, and we regret the impact this has had on the betting public. The health and safety of our equine and human athletes is our top priority and we are thankful for the safety of all involved."

It was a third win in the race for Appleby, who is champion trainer in Britain this year for the first time in all but name and was claiming his fourth Breeders' Cup triumph.

“It was a very peculiar chain of events and mentally very challenging for the horse, but I always felt he had the experience," the Moulton Paddocks handler said.

“The most important thing is that both horses are all right, and fortunately Modern Games pulled it out of the fire for us. He was actually under the pump a bit earlier than normal, but he picked up and kept finding.

“Albahr has some minor cuts and my vets are examining him. We were expecting the worst, but fortunately he’s OK.”

He added of the winner: “He will join our Guineas squad for next year. We will ship him back to the UK and winter away with him.”

Buick said: “There was a lot of confusion back there, but the horse did nothing wrong. They opened the front gate and he jumped out – he should have come of the back instead of the front.

“The guy that opened my gate pulled me out of the front and he told the officials what he did. Maybe there was a bit of confusion and panic, but my horse wasn’t harmed in any way. He was never touched.

“You could see how professional he was and he took everything in his stride.”

He added: “I don’t know why he was scratched, I was told afterwards. I knew he was going to run so I don’t want to focus on the whys and wherefores. It was out of my control. The booing was disappointing because he put up a very good performance.”

Modern Games prevented the home team winning all five Breeders' Cup contests on day one of the meeting.

Wesley Ward's Twilight Gleaming, runner-up in the Queen Mary at Royal Ascot, won the Breeders' Cup Juvenile Turf Sprint, while Pizza Bianca came from well off the pace to land the Breeders' Cup Juvenile Fillies Turf.

The two dirt races, featuring no raiders, were won by the market leaders. Echo Zulu enhanced her already tall reputation with a commanding victory in the Netjets Breeders' Cup Juvenile Fillies, while Bob Baffert was on the mark with Corniche.