Like many of Hern's best horses, Bustino was not highly tried at two. He made his only appearance in the Acomb Stakes at York in August and finished third.
1974: three-year-old season
As a three-year-old in 1974, the colt began by winning the Sandown Classic Trial from the future Epsom Derby winner Snow Knight, who was carrying five pounds more in weight. In the Lingfield Derby Trial he again defeated Snow Knight, this time at level weights. At Epsom, he seemed to be unsuited by the firm ground and finished fourth in the Derby, behind Snow Knight, Imperial Prince and Giacometti. Bustino was then sent to France for the Grand Prix de Paris at Longchamp Racecourse, in which he finished second of the eighteen runners, beaten two lengths by Sagaro. Back in England, he won the Great Voltigeur Stakes in August, beating Irish Derby winner English Prince. At Donacasterin September, Bustino started the 11/10 favourite for the St. Leger Stakes. He was assisted by his stable companion Riboson, who set a strong pace, before Bustino took the lead in the straight and won by three lengths from Giacometti.
1975: four-year-old season
Sent back to the track in 1975 at age four, Bustino won the Group One Coronation Cup at Epsom Downs Racecourse then was an integral part of what the British racing world and major newspapers dubbed the "Race of the Century."
Britain's "Race of the Century"
Bustino was up against a very solid field in the King George VI and Queen Elizabeth Stakes that was open to older horses. The participants included Eclipse Stakes winner, Star Appeal, Nelson Bunker Hunt's mare, Dahlia, one of the greatest female horses in world Thoroughbred racing history, and the three-year-old Grundy, a winner of both the Epsom and Irish Derbys. Trainer Dick Hern knew Bustino had the stamina for the 2,414 metre race and started two of Bustino's stablemates to set a blistering early pace designed to wear down Grundy. With half a mile left to run, Bustino and jockey Joe Mercer moved into the lead. He was ahead by four lengths by the time they entered the top of the straight when Pat Eddery on Grundy mounted a charge. The two horses began pulling away from the rest of the field and with a furlong left to run, Grundy passed Bustino, who soon retook the lead. Fifty yards from the finish line, Grundy fought back and recaptured the lead, holding off Bustino's continued furious effort to win by half a length with Dahlia another five lengths behind in third. The winning time of 2:26.98 beat the race record by almost two and a half seconds, a record that lasted for 35 years. As sometimes happens, a race of this nature took a toll on both horses. Grundy ran only once more without success, and Bustino never raced again. In The Observer newspaper's list of the "10 greatest horse races of all time," the match between Bustino and Grundy in the King George VI and Queen Elizabeth Stakes at Ascot Racecourse on 26 July 1975, was ranked number two: number one was the race between Quashed and Omaha for the 1936 Ascot Gold Cup. Bustino was being prepared for the Prix de l'Arc de Triomphe when he sustained an injury to his foreleg which ended his racing career. He was retired to stud with a valuation of £600,000.
Assessment
Bustino was awarded a rating of 136 by Timeform. A rating of 130 is considered the mark of an above average Group One winner. In their book A Century of Champions, John Randall and Tony Morris rated Bustino the eighty-seventh best racehorse of the 20th century and the thirty-eighth best British horse.
Stud career
Retired to stud duty, Bustino proved a very successful sire. His offspring include: