Bred and owned by the late Paul Mellon, trained by Ian Balding at Park House Stables in Kingsclere, near Newbury, and ridden, exclusively, by Geoff Lewis, Mill Reef won 12 of his 14 races between 1970 and 1972. In fact, his record of six consecutive Group One victories in 1971/72 stood for 30 years, until broken by Rock Of Gibraltar in 2001/02.
Named after the Mill Reef Club, a private members’ club on the island of Antigua in the West Indies, Mill Reef was an outstanding juvenile in 1970, winning the Coventry Stakes at Royal Ascot and the Gimcrack Stakes at York over 6 furlongs and the Dewhurst Stakes at Newmarket over 7 furlongs. He began his three-year-old campaign with victory in the Greenham Stakes, over 7 furlongs, at Newbury and, although beaten fair and square by Brigadier Gerard in the 2,000 Guineas, he would come into his own over middle distances as the season progressed.
Indeed, he displayed an excellent turn of foot to beat Linden Tree in the Derby at Epsom and subsequently beat the French colt Caro, the best older horse in Europe, by 4 lengths in the Eclipse Stakes at Sandown. Training Ian Balding later reflected, “He was going away from them in the last furlong; had it been over a mile and a half he’d have won by 10 lengths.”
Stepped back up to a mile and a half pulverised the opposition in the King George VI & Queen Elizabeth Stakes at Ascot, winning by 6 lengths, and finished the year with a 3-length victory over Pistol Packer in the Prix de l’Arc de Triomphe at Longchamp, breaking the track record in the process.
Mill Reef was kept in training as a four-year-old, winning the Prix Ganay at Longchamp and the Coronation Cup at Epsom, but was plagued by a virus and a swollen hock, before fracturing his left foreleg during a piece of work on the gallops at Kingsclere, which ended his racing career.