Is Constitution River what Aidan O'Brian has been waiting for?

For all that the extraordinary Aidan O’Brien has accomplished, some say he has never trained a truly great flat horse, but could that change when Constitution River lines up at York this month?

When it comes to O’Brien, whose legendary hurdler Istabraq was an undisputed jumps champion, there is a danger his best horses, to some degree, blur into one, but that’s probably because he’s trained so many.

Officially, Hawk Wing, with a rating of 133, is the finest he has had through his hands with crack miler Excelebration (130) next, but then it gets slightly complicated because their entire body of work doesn’t match up with some of his greats rated inferior.

Prix de l’Arc de Triomphe winner Dylan Thomas leads the way in that regard on 129, while Rock Of Gibraltar, Fame And Glory (both 128), Giant’s Causeway and Duke Of Marmalade (127) were other ultra-reliable, brilliant performers who bagged a host of top-level prizes.

Not one, however, captured the Derby, the contest O’Brien and the Coolmore partners he works for desire over everything else. That brings us on to Galileo, who might be the 56-year-old’s career-defining horse when one takes into account the incredible progeny he produced for connections.

He was not a star two-year-old, but carried his Epsom excellence into the Irish Derby and King George VI and Queen Elizabeth Stakes, and ended his career with a top-class mark of 129, but did he necessarily achieve more on the track than fellow Classic heroes Australia (127) and Camelot (124)?

They were better juveniles and Camelot, who came close to Triple Crown glory, was the joint-leading one of his generation, while he also had the speed to win the 2,000 Guineas, in which Australia ran well before demonstrating his ability over a distance shorter than the Derby’s in the Juddmonte International.

Incidentally, O’Brien has City Of Troy, his 2024 Derby winner, top of the pile and put his head on the chopping block saying so, which provided skeptics with a field day when the son of Justify was thumped in the 2,000 Guineas.

Unwavering in his view, the record-breaking trainer told the Racing Post this spring: “I wouldn’t have said those things about him unless I meant them.”

And he probably wasn’t far wide of the mark as City Of Troy was an unbeaten champion two-year-old who also bossed other bona fide events (the Eclipse and International) and ended up tied as the world’s best in 2024, although his rating of 128 wouldn’t take that honour regularly. It’s actually 1lb adrift of Rip Van Winkle, another Ballydoyle favourite who got his lofty figure for finishing second in a race, albeit one for the ages against Sea The Stars in the 2009 Eclipse.

Perhaps some of those names - and that’s without mentioning the likes of George Washington, So You Think, St Nicholas Abbey, a host of fine fillies and some star stayers - would have been remembered more favourably and fondly if they’d been trained by someone else, but, to these eyes, at least in Europe this century, only John Oxx (Sea The Stars) and Sir Henry Cecil (Frankel) have trained true champions who can do it all, so it’s hardly a stick with which to beat O’Brien.

He now has the chance to force a rethink on the theory if Constitution River topples dazzling Royal Ascot winner Ombudsman in the International at York on August 19.

Along with Bow Echo, he is the most exciting three-year-old around and oozed quality in the Prix du Jockey Club and Eclipse, but faces a horse threatening to be the greatest John Gosden, who trains in partnership with son Thady, has had; Ombudsman’s mighty mark of 131 makes him in the world’s best with superstar Hong Kong sprinter Ka Ying Rising in the latest rankings and is a level Golden Horn, Raven’s Pass and Enable never reached, so that’s the task Constitution River faces.

A self-described “dreamer” when it comes to bigging up his horses, O’Brien says his latest pin-up boy has “always been very special”, although cynics believe his words are a marketing gimmick to add value to his horses’ prospects as stallions.

It was, however, Ryan Moore who sent the hype machine into overdrive after the Eclipse, although there was an assist from the Ballydoyle maestro, who said: “Ryan said he doesn’t think he’s ridden a better horse.”

As measured as they come, Moore was reluctant to confirm he had made that statement, but hinted he thought the son of Wootton Bassett, who will receive weight from his older rival on the Knavesmire, was capable of better, which he will need to be against Ombudsman.

He is favourite at evens for the mouthwatering York clash, while you can get 7-4 about Constitution River, but don’t expect long odds about O’Brien hailing the latter as a true great if he does triumph - and he’d have every reason to do so.