CHANTILLY, France (AFP) — Master Irish trainer Aidan O’Brien swept the board in the French Derby (Prix du Jockey Club) as favourite Constitution River led home a 1-2-3 at Chantilly on Sunday.

It is the second time O’Brien has swept the placings in one of France’s historic races. Found led home two stablemates in the 2016 Prix de l’Arc de Triomphe.

Constitution Hill thundered home under Ryan Moore to beat Hawk Mountain and Montreal.

“One never thinks such things are possible, and when they do happen it is incredible,” said O’Brien.

O’Brien named a whole host of people, including the stable lass who looks after Constitution River, for their contribution to the win.

It was left to Christophe Soumillon, who rode the runner-up Hawk Mountain, to sum up 56-year-old O’Brien’s feat.

“It is an exceptional achievement,” said Soumillon.

In a remarkable day for the O’Brien family, Aidan’s son Donnacha trained the fourth horse home, A Boy Named Susie.

Constitution River overcame the odds of a terrible draw but was always up at the front with hi,s two stablemates.

Once Moore pushed the button he eased past the pace-setting Montreal and Hawk Mountain to give O’Brien his fifth Classic success of the campaign.

The French hosts’ best horses were simply not up to the challenge and trailed in their Irish rivals’ wake.

“That was a great performance,” said O’Brien. “He looked green but came home very well.”

Moore, like O’Brien winning his third French Derby, said he had not been too worried by having the widest stall of the 16 runners.

“Obviously we had a bad draw but I knew I had a good horse,” said Moore.

“It was a bit of a shock for him going right-handed but I knew he had the ability to get over these things. He is still a bit green but this was part of the learning process.

“He has a chance of staying further as he has a lot of pace, but he will get better.

“Aidan had them trained perfectly for the race.”

Constitution Hill’s co-owner Michael Tabor said he had not realised O’Brien had trained the first three home, as he only had eyes for the winner.

Having had time to absorb the triumph and O’Brien’s feat, Tabor said experience had taught him to soak up the moment immediately.

“Time flies and it is hard to enjoy such experiences,” he said.

“No one has a handle on life but when you are having fun, it flies by.