On a day when the reigning monarch was kept under medical supervision at Balmoral in Scotland after doctors became concerned for her health, the Quick Ride By Quickslide Handicap held special attention at the home of the Derby.
Sent off a 3-1 chance in what was the last race on the card, the Michael Bell-trained filly appeared to have matters under control throughout in the hands of apprentice jockey Benoit De La Sayette.
She went a length clear inside the final furlong and looked sure to oblige in the famous silks, but began to drift off the rail down the famous camber of the straight.
That allowed Richard Hannon's Mount Kosciuszko and Sam Hitchcott the chance to get a run up the rail and that pair hit the front on the line, winning by a short head.
Adayar ticks the boxes with perfect return at Doncaster
Adayar made the perfect return to action after nearly a year off the track in the Hilton Garden Inn Doncaster Conditions Stakes on Town Moor.
The first horse for 20 years to win the Derby and King George VI And Queen Elizabeth Stakes in the same season last year, the Frankel colt then went on to finish fourth in the Prix de l'Arc de Triomphe.
He was last seen when disappointing in the Champion Stakes just 13 days after his French run and for various reasons had been off the track since.
Having picked up a cough in the spring which caused him to lose condition, he missed the Coronation Cup, Royal Ascot, the Eclipse and the Juddmonte International and trainer Charlie Appleby was relieved to get him back on the track.
Only two rivals were brave enough to take him on, and one of those was his stablemate Dhahabi but the other, Andrew Balding's Masekela, did finish fourth in the Derby.
Is was Masekela who made the running but William Buick tracked him into the straight and it was simply a matter of when he went to the front.
In truth Adayar will have had harder pieces of work on Appleby's Moulton Paddocks gallops as he breezed to three and three-quarter length win, to reward those who backed the 2-7 favourite.
Paddy Power cut Adayar to 8-1 from 14s for the Champion Stakes and to 16s from 20 for the Arc.