Alan King's Tritonic dented some lofty reputations in the Haynes, Hanson & Clark Conditions Stakes at Newbury.
The race has unearthed some greats of the Turf down the years, including Shergar (1980), subsequent Prix de l'Arc de Triomphe hero Rainbow Quest (1983) and multiple Group One winner Nayef (2000), and all the pre-race talk this time was around John Gosden's Cape Palace.
Hugely exciting on his debut at Newcastle, the son of Golden Horn was sent off the 1-2 favourite to remain unbeaten, but with a furlong to run Frankie Dettori asked him to quicken and he found disappointingly little.
Richard Hannon's well-regarded Man Of The Night still had a chance at the business end, but it was King's Sea The Moon colt, sent off at 12-1, who found plenty to pull away and win by a length and a half, with another length and a quarter back to Cape Palace.
It was the 150th winner of the campaign for champion-elect Oisin Murphy, also successful earlier on the card and currently riding on the quest of a wave.
King said: "It has taken us by surprise, but we have always loved him. He won well at Ffos Las, but I was disappointed that the form hadn't really worked out. We thought this was a nice place to come. I'm actually a bit shocked.
"I thought it would be about next year and I was hoping that I wasn't embarrassed today by running in this. He is so laid-back and he does enough. He has won with his ears pricked. It's lovely as we probably haven't had a two-year-old like this before, so it is exciting."
He went on: "Oisin said he could run once more and I said he has only got one flash entry, so he said that's his race if we want to run him again. We will see how he is. I said today he will either finish today or have one more.
"That might be pie in the sky (Verterm Futurity Trophy at Doncaster), but he is fairly good. It's a good job I didn't geld him! I can't think that I've had a runner in a Group One before."
On ground preference for his winner, King added: "The slower (the ground) the better for him, but Newbury have done a good job as they have put a lot of water on and it's beautiful ground. I wouldn't want to run him on quick ground.
Thady Gosden, assistant to his father, said of the beaten favourite: "Frankie said he was a little bit keen at the start of the race and therefore he didn't finish out properly. He ran his race a little too early.
"It was only his second run and he is still inexperienced. It was just one of those things. He is definitely talented, so hopefully it will be onwards and upwards next time."