Darkness Falls proved the stronger to narrowly beat Desert Castle in the Dewhurst Stakes at Newmarket.
The pair led the five runners in the race for the line and Darkness Falls, ridden by Ryan Moore, held off favourite and previously unbeaten Desert Castle, who had William Buick on board.
Aidan O’Brien-trained Darkness Falls had dropped back to seven furlongs from a mile-and-one after winning the Golden Fleece Stakes at Leopardstown last time out.
“He’s a really good colt,” Moore told ITV Sport. “It feels like there’s more in the tank.
“How far he’ll go I don’t know, he has a lot of pace.”
O’Brien added: “It was a big call to come here and it’s incredible to bring a horse back from nine furlongs to win a Dewhurst.
“We’ve always loved him and he’s always had a lot of class. Ryan gave him a brilliant ride and I’m so grateful to win this for everyone, he’s very exciting.
“We came here to give him the experience with a view to the Guineas and we were always going to find out plenty.
“It was a massive ask to bring him back to seven furlongs, it was a tough nine at Leopardstown last time and he has so much class obviously.
“He’s so exciting, as you saw what he did over nine furlongs and I don’t think he’ll have any problem going further either, he has a lot of quality.
“When they have as much class as he has they can do anything and the Triple Crown is the dream.”
The Triple Crown covers the 2,000 Guineas, the Derby and the St Leger, with Nijinsky – in 1970 – the last horse to win all three races in a year.