Aidan O’Brien turned Sunday’s French Derby into a historic Irish rout as Constitution River led home a clean sweep of the places in the €1.5 million Qatar Prix Du Jockey Club at Chantilly.Constitution River overcame a perilously wide draw to win under Ryan Moore from his stable companions Hawk Mountain and Montreal. Remarkably the first four horses in the historic race were Irish as A Boy Named Susie, trained by O’Brien’s son Donnacha, filled fourth place.The result echoed O’Brien’s unprecedented clean sweep of the places in the Prix de l’Arc de Triomphe a decade before when Found beat Highland Reel and Order Of St George. That too took place at Chantilly, while the Arc’s traditional home at Longchamp was being redeveloped.Considering the pre-race uncertainty around Constitution River’s unfavourable draw in stall 15 of 16, O’Brien’s Ballydoyle team pulled off a tactical masterclass in ultimately making the first major European Derby of 2026 relatively straightforward. After initially racing apart from the field for the first couple of furlongs, Moore gradually slid in towards the pack around Chantilly’s turning track. By then Montreal had gone to the front, closely followed by Hawk Mountain, and from there nothing else got a look in.All three Irish colts had just a single start this season prior to the Jockey Club and Constitution River briefly showed signs of inexperience early in the straight. Moore was pushing from some way out but after all three horses were in a line a furlong out, the 15-8 favourite ultimately won with some authority by three parts of a length. It was a third Jockey Club victory in six years for O’Brien following St Mark’s Basilica (2021) and Camille Pissarro last season. Constitution River is just the fifth Irish-based horse to win the French Derby. The Irishman’s focus will now switch to Saturday’s Epsom Derby and a potential 12th success in English racing’s blue riband. His Benvenuto Cellini is favourite for that. However, the sense that Constitution River tops Ballydoyle’s three-year-old pecking order won’t have been shaken by his Classic success. Moore is famously tough to impress but emerged from his own third French Derby victory to say his latest Classic winner could either go down or up in trip in future. “I think he’s quite a rare horse really,” the English rider said. MV Magnier, son of the Coolmore kingpin, John Magnier, also commented: “Aidan thinks he could be something different. He has to keep doing it, but he’s done it today against the odds.”O’Brien himself typically tried to deflect attention elsewhere, although even by the standards of having already rewritten racing’s record books during his 30 years at the helm in Ballydoyle this was a landmark result. “He’s a big, powerful horse with loads of scope. We always thought he was very exciting and we still think he is, and we think the second and third are two very good horses. Then Donnacha’s horse was fourth and we knew Donnacha really fancied him. So what can I say? I’m over the moon.”