Galway jockey Rossa Ryan rode 150/1 shot Valiant Force to victory for trainer Adrian Murray in the Norfolk Stakes, the opening race at Royal Ascot on Thursday.
It is the joint biggest priced winner ever at Royal Ascot along with Nando Parrado three years ago.
"He's unbelievable, just unbelievable," Westmeath-based Murray told Sky Sports Racing.
"It's not [a shock to me]. He was only half a length beaten by His Majesty on his first run. The second run, you can totally disregard. I couldn't believe the price that he was, just couldn't believe it."
𝟏𝟓𝟎/𝟏! 🤯
Valiant Force shocks all to win the Norfolk!#RoyalAscot | #VMTVRacing pic.twitter.com/SkEjKOMgoF— Virgin Media Sport (@VMSportIE) June 22, 2023
Valiant Force moved into second by halfway, and then led with two furlongs to go as he held off second-placed Malc and favourite Elite Status.
"To be fair to the lads, they were confident he'd run a big race," Ryan told ITV Racing.
"If you took away his last run in the Curragh when he was on his own, he's run a stormer first time in a listed race - that's how much they thought of him.
"He's bred well, bred to be a sprinter. He's something else to look at. He was nearly a standout in the paddock.
"He jumped well [out of the stalls], did everything right. I was just in a rhythm, and when I took the lead off Gavin inside the two, I was always in a rhythm.
"I probably could have won further if I had someone to come at me with a run. He's got the job done."
The horse is owned by football agent Kia Joorabchian's Amo Racing.
"We really like this horse a lot," Joorabchian told Sky Sports Racing.
"He got an unfortunate run in Ireland [at the Curragh]. He was left on his own on the right side. I think Colin (Keane, the jockey) did great by not killing him at that time, keeping him back and saying 'OK, this race is gone'. It probably set him up for this."
"To be fair to the lads, they were confident he'd run a big race."@Rossaryan15 on Valiant Force after they won the Norfolk Stakes at a huge 150/1! 👏
What a result for @AMurrayRacing and the team! ☘️#RoyalAscot | #VMTVRacing pic.twitter.com/RbAqGA3fW1— Virgin Media Sport (@VMSportIE) June 22, 2023