Authentic upstaged race favourite Tiz The Law to win the Breeders' Cup Classic at Keeneland in Kentucky and give trainer Bob Baffert a record-extending fourth success in the $6 million showcase.
In one of the strongest fields for years, Hall of Fame jockey John Velazquez piloted Authentic to victory by 2-1/2 lengths in a race that was held in front of a mostly empty grandstand due to the Covid-19 pandemic.
Authentic, who won the Kentucky Derby, was in front by the first turn of the 1-1/4 mile race and never relinquished his lead as he pulled away during the final stretch.
"I was sort of surprised, you know," said Baffert, who had a trio of entries in the race.
"But he's a quirky horse. He'd been working unbelievable, they all were. I think Johnny really knows him well and once he got them in that rhythm, he's just getting better and better."
Improbable, also trained by Baffert, finished second while Global Campaign was third in a field that also included Belmont Stakes winner Tiz the Law and Maximum Security, who finished first in the 2019 Kentucky Derby but was disqualified.
While Velazquez counts three Kentucky Derby wins among his five Triple Crown race wins, the victory marked the first time he triumphed in a Breeders' Cup Classic.
"I've been chasing this race for quite a while," said Velazquez. "For me, it was just incredible. What a feeling. I don't know what to say."
Aidan O'Brien secured his first Breeders' Cup Mile in stunning fashion as Order of Australia led a one-two-three finish for the Irish trainer in the $2 million race in Lexington.
Order of Australia's place in the field was only secured after the William Haggas-trained One Master was scratched through injury.
Jockey Pierre-Charles Boudot, originally slated to ride One Master, got his first ride on Order of Australia after jockey Christophe Soumillon was ruled out by a positive Covid-19 test in Kentucky.
Boudot made the most of his chance, grabbing his second win of the day after piloting Audarya to victory in the Filly & Mare Turf.
"It's a dream come true," said Boudot. "It is only by chance to get these rides and I'm sorry for Ioritz Mendizabal [previous rider of Audarya] and Christophe Soumillon.
"It's a difficult situation with Covid, but I was given two nice opportunities."
Breaking from the outside post in the field of 14, Order of Australia raced in the clear through the first turn and down the backstretch in fourth place behind the pace set by Halladay and Factor This.
In the stretch, Halladay saw off Factor This but couldn't hold off the run by Order of Australia.
"Order Of Australia is a fast horse, the mile is very good for him and the good ground was perfect," Boudot said. "He gave me a nice turn of foot but when he got to the front, he's a tricky horse as he needs some help to concentrate.
"I'm over the moon."
Circus Maximus, ridden by Ryan Moore, finished three-quarters of a length in front of Lope Y Fernandez with Frankie Dettori in the irons.
It was a 13th Breeders' Cup win for O'Brien, who also saddled runner-up Circus Maximus and third-placed Lope y Fernandez.
"First three home is unbelievable," said O'Brien assistant Pat Keating. "It's a huge team effort and good people involved all the way along the line. They're good horses and three good jockeys."