ORDER OF AUSTRALIA led home a one-two-three for trainer Aidan O'Brien with a shock victory in the Breeders' Cup Mile at Keeneland.
The three-year-old colt only got into the race after One Master was scratched on Thursday and was sent off an unconsidered 73-1 outsider.
His jockey Pierre-Charles Boudot himself only got the ride after Christophe Soumillon tested positive for Covid-19 and completed an unlikely double after he also replaced Ioritz Mendizabal on Audarya in the Breeders' Cup Filly & Mare Turf.
Order Of Australia had only won two of his seven previous races and had fallen short in two previous attempts at the top level - but he came good when it mattered, to give O'Brien his first win in the race.
Halladay made the running until the straight, where there was all to play for until Order Of Australia swept on the outside to take the honours under another confident ride by Boudot.
The son of Australia kept on to hold his stablemates Circus Maximus and Lope Y Fernandez, giving Ballydoyle a remarkable clean sweep.
Kameko, the 2000 Guineas winner, had every chance under Oisin Murphy but finished out of the places, as did Irish Guineas victor Siskin.
O'Brien said: "We always thought that as the season went on a mile on fast ground on a flat track would be ideal for Order Of Australia.
"He's a horse that quicken very well and he had been working well."
Boudot - who would have ridden the William Haggas-trained One Master - said: "I spoke to Aidan, who was very confident about this horse. He said I should be positive and as he is fast and a proper horse I should ride him from on the pace.
"He travelled very nicely throughout and produced a good turn of foot when I asked him."
He added: "Christophe gave off a positive test for Covid and my horse got into the race as One Master was a non runner.
"It's a dream come true for me and I'm thankful to my agent, who must be one of the best in the world."
Kameko's rider Oisin Murphy said: "I got him into the perfect position that I wanted going down the back. I thought the track would suit him and that he would travel, but he didn't pick up.
"While this is disappointing, it doesn't indicate how good he is. It's just that he has trained hard all year, he'll make a wonderful stallion."
Colin Keane said of Siskin: "He behaved himself down at the stalls, but gave me the impression in the race that the year had caught up with him."
Elsewhere, Kentucky Derby hero Authentic gave Bob Baffert a fourth Breeders' Cup Classic success at Keeneland.
The three-year-old made virtually all the running and dug deep when needed to hold his year-older stablemate Improbable in the closing stages.
John Velazquez - celebrating his first win in the Classic - soon had Authentic in pole position, but he was shadowed by another stablemate, Maximum Security, with his old adversary Tiz The Law not far behind.
There was all to play for at the top of the straight, where Authentic pulled out more when challenged by Improbable and would not be denied. Global Campaign was third.
Baffert - recording his 17th career Breeders' Cup victory - said: "It was really disappointing about the Preakness (second to Swiss Skydiver), he's a quirky individual but Johnny knows him so well and the horse is getting better and better. He'd been working unbelievable and Johnny knows him well and got him in a rhythm.
"After two races, the Santa Anita Derby and the Preakness, he came back blowing, and I didn't have him as sharp as he should have been and we needed to tighten the screws. I was proud of my horses in the race and it was a good run from Improbable, but I think you saw the best Authentic today.
"I told Johnny 'that is the horse you rode in the Derby' - he's spring-loaded and you can ride him with confidence and be aggressive. He's getting better and better. He's caught up with the older horses.
"I knew I had him right back to his best, as he'd matured and was making right, but for some reason when I looked at the Tote board he was showing 5-1.
"He's just an unbelievable horse and I'm so happy for the connections, especially Wayne Hughes. Those are his colours. We were hoping those colours would be in the Kentucky Derby, but it's great the way it's ended. We would have loved a one-two-three.
"I was proud of my horses and what a way to end after what I've gone through this year. I love this sport and it's just a great day."
Asked about the future for Authentic, Baffert said: "I would love to have the horse back in the barn, but unfortunately I don't get a vote on that one. Whatever happens he has been a saviour."
Velazquez said: "We talked about tactics and agreed to take advantage and get him to the rail in front. After that he did everything I wanted him to do.
"I didn't think there was too much speed in the race and once I got him running past the wire for the first time it was looking good for us. The horse came back (from the Preakness) and sealed the deal - he was the best horse in America today.
"I've been chasing this race for quite a while and to have the opportunity to do it and to win it is incredible. What a feeling."