Whoever rode Charlottown in his Derby Trial, I thought, got replaced by Breasley. Must have been Hutchinson. The earliest jocking off I know of was Piggott jocking off Mercer in the Coronation Cup on Nagami. Apparently Harry Wragg got very upset and Mercer would never ride for Mrs Plesch again. I suppose the famous jocking off was Roberto with Weary Willie (Bill Williamson) being the victim.
That's right Bustino. Hutchinson came in for a lot of criticism for his ride in the trial and Scobie took the mount in the Derby