John Ingles with four great racehorses ridden by Joe Mercer

Brigadier Gerard (Timeform rating 144)

While Joe Mercer’s career in the saddle spanned four decades and resulted in more than 2,800 winners, if there’s one horse which defined his career it was the outstanding Brigadier Gerard whom he partnered in all 18 of his starts, winning 17 of them. This year marks the 50th anniversary of Brigadier’s Gerard’s unbeaten three-year-old season which he began by winning a memorable 2000 Guineas, beating another outstanding colt in Mill Reef, and ended in the Champion Stakes. Brigadier Gerard proved better still at four, when his wins included the Eclipse, King George and a second Champion Stakes. Only Frankel has had a higher Timeform rating among British-trained Flat horses.

Bustino (136)

Four of Mercer’s eight British classic victories came in the St Leger, including with Brigadier Gerard’s son Light Cavalry. But the best of that quartet was the 1974 winner Bustino, trained, like Brigadier Gerard, by Dick Hern. The Derby was the one classic that evaded Mercer, with Bustino finishing fourth to 50/1 shot Snow Knight at Epsom, a horse he had beaten twice previously that year. ‘Bustino’, remarked Racehorses of 1974, ‘is the sort of honest, resolute workman that responds well to the strong, direct style practiced so successfully by his stable-jockey.’ The following season’s King George at Ascot provided a perfect example, though Mercer and Bustino had to settle for second place to Pat Eddery and Grundy in a finish still regarded as one of the best in a major Flat race.

Le Moss (135)

Mercer rode two outstanding but very different horses during his time with Henry Cecil’s stable. One of those was Le Moss, described by Timeform as ‘a phenomenon among racehorses: he’s not the best long-distance horse we’ve seen, but if there is such a thing as a top-class racehorse that stays for ever Le Moss is probably the closest to him we have encountered since that great out-and-out stayer of the mid-‘forties Marsyas II.’ Together, Mercer and Le Moss landed the stayers’ triple crown in 1980, Le Moss making all the running in the Gold Cup at Royal Ascot, Goodwood Cup and Doncaster Cup, all of which ended in thrilling duels with Ardross. Le Moss had completed the same treble the previous season, though Lester Piggott had been in the saddle for his Ascot win.

Kris (135)

Mercer was champion jockey in 1979, a season in which miler Kris won seven of his eight races, his only defeat coming when second to Tap On Wood in the 2000 Guineas. His other wins that year included the St James’s Palace Stakes, Sussex Stakes and Queen Elizabeth II Stakes, all races which Mercer had also won with Brigadier Gerard – no horse had dominated the miling division in Britain in quite the same way since Brigadier Gerard at the start of the decade.