Aidan O'Brien's Curragh maiden scorer Ruler Of The World faces four opponents in the MBNA Chester Vase on Thursday.
The Ballydoyle handler has saddled three of the last six Chester Vase winners in Soldier Of Fortune (2007), Golden Sword (2009) and Treasure Beach (2011).
This son of Galileo is a half-brother to multiple Group One winner Duke Of Marmalade and looked the part when making a winning debut in his homeland in early April.
He now tests his Derby claims in this mile-and-a-half Group Three, with Ryan Moore taking the ride.
The highest-rated horse in the line-up is the Andrew Balding-trained Havana Beat, fourth in a valuable sales race at Newmarket three weeks ago.
Champion trainer John Gosden is represented by Newbury winner Feel Like Dancing, while Richard Fahey, who struck gold 12 months ago with Mickdaam, runs Gabrial's Kaka.
The small field is completed by Mark Johnston's Mister Impatience.