Galileo Chrome provided jockey Tom Marquand with a remarkable first Classic victory in the Pertemps St Leger at Doncaster.
Marquand discovered he would be riding Joseph O'Brien's colt barely 24 hours before the big race - after regular jockey Shane Crosse became unavailable because of a positive test for Covid-19.
While Crosse must therefore begin his period of isolation in Ireland, Marquand took his place and prevailed by a neck at 4-1 from 16-1 shot Berkshire Rocco, trained by Andrew Balding.
Pyledriver appeared set to make a bold bid for glory before wandering from a true line out on his own on the far side, eventually finishing third, a length further back.
Just behind in fourth was Santiago, who was sent off the 5-2 favourite for Aidan O'Brien and Frankie Dettori.
