Europe’s most commercially relevant Derby takes place in Chantilly on Sunday. The Qatar Prix Du Jockey Club isn’t the most historic Derby. It mightn’t even be the most coveted. It certainly isn’t the most high-profile, nor is it worth the most prizemoney. But in terms of shaping the thoroughbred breed, France does what it says on the Derby tin. That’s because it isn’t run at a mile and a half. Instead, the Jockey Club is an extended mile and a quarter, or 2,100 metres. That’s just 300 metres less than next week’s Epsom Derby or the Irish Derby at the Curragh 22 days afterwards. In bloodstock valuation terms, though, those 300 metres represent a chasm. When the French opted to cut their Derby test from a mile and a half in 2005, even then it was an acknowledgment of commercial reality. What had been the ultimate classic distance for centuries was already unfashionable. Once the definition of thoroughbred class, the capacity to carry speed over 12-furlongs became code for stamina and there’s no more poisonous word in the bloodstock game here.It’s why Constitution River lines up at Chantilly this weekend rather than waiting for Epsom. Results have a way of confounding expectations but as of now Constitution River is widely regarded as Aidan O’Brien’s best three-year-old colt. He’s got a touch of stardust. A French Derby success will automatically make him a hugely valuable stallion prospect. Winning at Epsom won’t.It’s a sorry fact of racing life, but the Epsom Derby’s historic role as the race that shapes the thoroughbred is redundant. It is no longer the ultimate maker of champions that go on to shape the breed. Bloodstock fashion has dated it, and if the sport’s central participants don’t buy the hype any more, why should anyone else?No one’s more central than Coolmore Stud’s kingpin John Magnier. It’s ironic how the bloodstock game’s ultimate fashion house has been keeping the Derby show going at Epsom and the Curragh because Coolmore’s transformation of the breeding industry has been rooted in delivering speed. Without Magnier’s staunch support of both races they would have long since become hollow tests. But the Constitution River call smacks of business is business.Coolmore’s wealth of talent means Benvenuto Cellini is likely to start favourite at Epsom in eight days. But it’s hard to ignore the significance of his stablemate’s switch to Paris. This is a colt sure to stay 10-furlongs and with a shot at getting 12. It used to be an ideal scenario heading to Epsom. In the past Constitution River would have gone there. But not this time. Christophe Soumillon rides Benvenuto Cellini to Champions Juvenile Stakes win at Leopardstown in 2025. Photograph: Tom Maher/©INPHO Another irony is how Coolmore’s most prepotent stallion of the last two decades was a classic mile-and-a-half racehorse. Galileo wound up transforming the breed but before his progeny started winning all round them his commercial appeal as a dual Derby and King George winner was limited. He was an exception to prove the rule.Coolmore retired Los Angeles to stud last winter. A Group One winning two-year-old and an Irish Derby winner at three, he even scored at 10-furlongs in the Tattersalls Gold Cup as an older horse. But he’s been banished to the National Hunt sire ranks alongside four other Epsom Derby winners of the last decade: Golden Horn, Harzand, Wings Of Eagles and Masar.Coolmore has won the last three Derbies at Epsom. Both Auguste Rodin and City of Troy were Group One winning juveniles and as with so many modern Derby winners spent much of their subsequent careers proving they weren’t “just” mile-and-a-half horses; last year’s winner Lambourn already looks to be damned as being just that.Ryan Moore on St Mark’s Basilica comes home to win the Irish Champion Stakes in 2021. Photograph: Caroline Norris/©INPHO