Despite not winning the Grand National in 13 attempts - finishing second on Badanloch in 1960 - or the Cheltenham Gold Cup, Mellor is considered by many in the horse racing world as one of the sport's greats.
He guided Stalbridge Colonist to victory over great Irish racehorse Arkle in the 1966 Hennessy Gold Cup, becoming one of the few riders to manage the feat.
Born to a timber merchant in Manchester, Mellor secured his first win at 16 on Straight Border in Wolverhampton before tasting success for the first time as a professional on Wirswall Prince at Ludlow in 1954.
He retired in 1971 having ridden 1,035 winners over jumps in Britain with another nine victories in Ireland.
He later trained both Royal Mail (1980) and Lean Ar Aghaidh (1987) to victories in the Whitbread Gold Cup. Both the horses managed third-place finishes in the Grand National. (Reporting by Shrivathsa Sridhar in Bengaluru; Editing by Hugh Lawson)