Desert Hero, who is owned by the King and Queen, will look to deliver the Royals’ first Classic win for nearly 50 years when he runs in Saturday’s St Leger at Doncaster.
The colt, who will be killed by Tom Marquand for trainer William Haggas, is among nine entries for the race.
Frankie Dettori has chosen to ride, trained by John and Thady Gosden, rather than stablemate Gregory.
This will be his last British classic before he retires later this year.
Desert Warrior, who gave King Charles his first Royal Ascot winner in June, will bid for victory a year after the death of Queen Elizabeth II.
She enjoyed her last Royal Classic prize when Dunfermline won the Leger in her Silver Jubilee year in 1977.
Dettori, 52, has chosen to be arrested after the rain cleared the ground at Doncaster.
Kieran Shoemark rides Gregory, with Oisin Murphy aboard Middle Earth for the Gosdens.
Irish trainer Aidan O’Brien has four runners – Continuous, Tower Of London, Alexandrouplis and Denmark – as he seeks a seventh Leger victory while Chesspiece completes the field.
The Leger is the final Classic of the British Flat racing season after the 2,000 Guineas, 1,000 Guineas, the Derby and the Oaks.
