Changingoftheguard threw his hat into the Derby ring with a thoroughly impressive display in the Boodles Chester Vase.

Trainer Aidan O'Brien had saddled a record nine previous winners of the Group Three contest, with his Ruler Of The World the last horse to follow up at Epsom in 2013.

O'Brien already houses the ante-post favourite for the premier Classic in the form of Saturday's 2000 Guineas third Luxembourg.

And while the previously unbeaten New London was the colt expected to emerge as perhaps Luxembourg's biggest threat with victory on the Roodee, Changingoftheguard had other ideas.

Sent straight to the lead by Ryan Moore, the 100-30 chance soon built up a handy buffer over Charlie Appleby's prohibitively priced 4-11 shot New London.

It was clear from before the home turn that the market leader was struggling to bridge the gap and Changingoftheguard galloped all the way up the straight to pass the post six and a half lengths clear.

Paddy Power slashed the winner's Derby odds to 8-1 from 50-1, while New London is out to 14-1 from 5s.

"He was impressive there and we always thought he'd stay well," said O'Brien.

"He was just chinned in his maiden at Punchestown before he then went and won his maiden really well at Dundalk.

"There was no doubt on our part that he would take a step forward from that and improve for going up in trip.

"The one thing we weren't sure about today was the ground when it rained as he's such a fluid mover, but he seems to have handled it fine.

"We were delighted with the run and I think off the back of that, you'd have to say he'd go to Epsom now."

Alex Merriam, Appleby's assistant, could offer no excuses for the beaten favourite.

He said: "William (Buick) said he never felt happy.

"We're not blaming the ground or the track, there's not much we can say really.

"This is what trials are all about, we'll see what happens, he was just beaten by a better horse today."

Buick said: "No excuses, he's got a lot to learn."