The Charlie Appleby-trained Hurricane Lane put aside any stamina fears with a clear-cut victory in the Cazoo St Leger at Doncaster.
The odds-on favourite travelled sweetly for William Buick in mid-pack as Hollie Doyle took them along on Interpretation, before cruising to the front a couple of furlongs out.
He quickened in great style in the famous Doncaster straight, soon settling matters without having a hard race.
Richard Hannon's Mojo Star (8/1), who had finished in front of the winner in the Derby at Epsom earlier in the season, tried in vein but Hurricane Lane was far too classy, readily coming away from his old rival to add to his top-class victories in the Irish Derby and Grand Prix de Paris, scoring by two and three-quarter lengths.
Aidan O'Brien's 28/1 chance The Mediterranean stuck to his task gamely in third but it was all about Hurricane Lane, who was immediately cut to 5/1 from 8/1 by Sky Bet for the Prix de l'Arc de Triomphe.
Appleby was winning the Leger for the first time in his training career, though owners Godolphin were claiming their seventh success in the oldest Classic. It was a third victory in the race for Buick, following back-to-back wins with Arctic Cosmos and Masked Marvel for John Gosden in 2010 and 2011.
“It was easy. He was the class in the race. It worked out beautifully. You never know until you go this far with a three-year-old,” Buick told ITV Racing.-
“He took me into the race so nicely and he’s got that turn of foot at the end. He’s a great horse.
“It was lovely to win the Leger with him. It’s been a fantastic season. This is what everyone at home strives for.
“I knew I was on the best horse. It was just a case of keeping it smooth.”
A delighted Appleby said: “It was a fantastic performance. Congratulations to Sheikh Mohammed and team Godolphin. It’s great to win any Classic but to win the final Classic, it’s historic, so it’s extra special.
“William said it was a dream race. He had the perfect pitch and all the room he needed and the great thing about this horse is he quickens. He’s got a gear change. You couldn’t have been more comfortable watching it all the way round.
“The ground isn’t key to him but he is more comfortable under these conditions on the slower side.
“I thought it was a great performance and Derby form was franked as well with Mojo Star running a great race. It’s got strength in depth which is what we want to see in a Classic.
“This horse has given us a couple of days where he has challenged us - he’s a boy - and he likes to do things his own way in the mornings sometimes. He takes a bit of managing just to get his shoes on in a morning.
“The Arc is on everybody’s mind. I’ve spoken to His Highness. Everyone is delighted and I think it is something we will keep an eye on but let the dust settle. I see no reason why we wouldn’t potentially turn up.
“As for next year with him and (Derby winner) Adayar, that is for everyone to talk about towards the end of the season after the Arc.
“His Highness is such a great sporting man and he loves to see his horses stay in training. We have seen so many of the greats from Godolphin down the years and I’m just fortunate I’m bringing a couple of them along myself."
