Ryan Moore has been confirmed to ride Kingston Hill in Wednesday's Great Voltigeur Stakes at York.
Trainer Roger Varian has kept his options open with the grey, who was also entered in the Juddmonte International on the same card, after finishing fourth in the Coral-Eclipse last time.
Main opponents to Kingston Hill look to be Hartnell, viewed as a Ladbrokes St Leger candidate by trainer Mark Johnston after victories in the Queen's Vase and Bahrain Trophy, and Sir Michael Stoute's Gordon Stakes winner Snow Sky.
Aidan O'Brien will bring across both the impressive Tipperary scorer Granddukeoftuscany and Indian Maharaja.
Observational is given another chance to stake a claim by Roger Charlton, having run moderately in the Gordon Stakes, while Postponed is tested further after winning a Hamilton Listed race.
Marzocco, Odeon and Red Galileo complete what is usually regarded as the strongest St Leger trial.
