Chester Vase victor Changingoftheguard books Derby ticket

Aidan O'Brien also saddled the winner of the Weatherbys Bloodstock Pro Cheshire Oaks where Thoughts Of June dominated from the front

Changingoftheguard powers to victory in the  Boodles Chester Vase for trainer Aidan O'Brien. Picture: Healy Racing

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 3 contest, with his Ruler Of The World the last horse to follow up at Epsom in 2013.