Ruler Of The World provided Aidan O’Brien with a fourth Investec Derby and maintained his unbeaten record under Ryan Moore at Epsom — with favourite Dawn Approach finishing last.

Dawn Approach failed to settle from very early on and Kevin Manning felt he had no option but to take up the running on the approach to Tattenham Corner, with the writing being on the wall some way out.

Ruler Of The World (7-1) showed a smart turn of foot to go clear, but Battle Of Marengo, Galileo Rock and Ocovango all set off in pursuit. The gap was closing at the line as Libertarian flashed home to claim second with Galileo Rock in third.

In the early stages Joseph O’Brien on Battle Of Marengo set a pedestrian gallop and with Dawn Approach wide with no cover and still pulling, Manning was forced to play his hand early.

Moore had the eventual winner just on the outside of Ocovango as the pace quickened, who was squeezed for room. Galileo Rock was handy throughout and stuck to his task gamely, outrunning his big price, but arguably the horse to take from the race was the unheralded runner-up, who was catching the winner with every stride, going down by a length and a half.

“We’re just so lucky, we get these incredibly-bred horses and even before they are mated the dream is for this to happen,” said O’Brien. “The owners understand the game so much, they are given all the information and usually come up with a plan and we try and carry it out.

“All the jockeys had their own plan and all the horses were doing their own thing and that is just the way it ended up. This horse was impressive at Chester (winning the Chester Vase) and won like a very good horse.”

Moore said: “It’s incredible, we’re very privileged to be in the position we are. I wanted to be a bit closer, but I just didn’t get away very well and it was a very messy race.

“I had no option but to go on when I did, I knew he’d stay the trip very well but I got there a bit soon and he was very green. He’s improved a lot from Chester and he’ll get further. He’s got a really likeable attitude.

“I knew the others were coming because I’d gone too early, but he really toughed it out and showed a very good attitude.” He added: “I’m very lucky to be in this position and on these horses. This is the most important race for me.”

Karl Burke, assistant trainer to his wife, Elaine, said of Libertarian: “He’s a big unit but he’s very athletic and I’ve never seen him lose his balance. Once he started making ground I thought he might be fourth or fifth, but then he really got going inside the last furlong and with 50 yards to go I thought he might get second, although he was never going to win.

“Stamina was never going to be an issue for him and why wouldn’t we take on the winner again in the Irish Derby, the Curragh would be much more up his street but he will have to be supplemented.”

Jim Bolger said of Dawn Approach: “Kevin said he jumped out all right and was was OK for about 10 strides but then he grabbed hold of the bridle and from then on he was more or less out of control. He’d been running over a mile where they’d been jumping out and going a good pace and Kevin could just let him bowl.

“I doubt he’ll be running over a mile and a half again.”