1973: three-year-old season

Ace of Aces was unraced as a two-year-old before beginning his racing career in 1973. He showed some signs of ability, winning one minor race and only once finishing out of the first four in seven starts. He was tried in blinkers on more than one occasion.^[1]

1974: four-year-old season

Ace of Aces finished second in his first two races as a four-year-old and then acted as a pacemaker for his more illustrious stablemate Dahlia in the Prix Ganay at Longchamp Racecourse on 5 May. After winning two minor races, the horse contested the Prix du Chemin de Fer du Nord at Chantilly Racecourse on 12 June and started the 4.6/1 second favourite in a thirteen-runner field. Ridden by Bill Pyers he won decisively by two and a half lengths from Gay Style. On his next appearance, Ace of Aces finished second to El Rastro in the Prix de la Porte Maillot, with the British gelding Boldboy in fourth. In early July he was sent to race in England and finished unplaced behind Coup de Feu in the Eclipse Stakes over ten furlongs, tiring badly after taking the lead on the final turn.^[1]

In late July, Ace of Aces was sent to England again to contest the Group One Sussex Stakes over one mile at Goodwood Racecourse. Ridden by the British jockey Jimmy Lindley he started at odds of 8/1 against nine opponents including Averof (St James's Palace Stakes), Habat (Middle Park Stakes), Pitcairn (runner-up in the Irish 2,000 Guineas) and Mount Hagen (third in the Eclipse Stakes). Lindley held the colt up towards the rear of the field as Averof set the pace from Mount Hagen and Habat. Mount Hagen went to the front in the straight but Ace of Aces made rapid progress to take the lead approaching the final furlong and drew away to win by two lengths from Habat. Ace of Aces returned to France two weeks after his Goodwood triumph but ran poorly to finish ninth of the ten runners behind Nonoalco in the Prix Jacques Le Marois. He was then sent to Germany for the Oettingen-Rennen over 1600 metres at Baden-Baden later in August. He was partnered by Lester Piggott and won by a neck from the British-trained Flintham, to whom he was conceding eight pounds.^[1]

In Autumn, Ace of Aces ran twice against top class opposition at Longchamp Racecourse. On 29 September, ridden by the Irish jockey Pat Eddery, he finished fourth behind Mount Hagen, Northern Taste and Lianga in the Prix du Moulin over 1600 metres. A week later he was brought back in distance and matched against specialist sprinters in the Prix de l'Abbaye over 1000 metres. He was held up by Piggott before finishing strongly but failed by a neck to overhaul the three-year-old Moubariz.^[1]

Ace of Aces achievements in 1974 had an indirect, but long-term impact on Thoroughbred racing. It was whilst discussing the Kentucky-bred's emphatic victory in the Sussex Stakes that John Magnier and Robert Sangster decided to target the major American yearling sales^[5] with a view to developing future breeding stallions. Over the subsequent decades, this strategy led to the global success of the Coolmore Stud.^[6]