Gosden stands between O'Brien and unique Triple Crown prize

Times Up (centre) wins the Doncaster Cup for trainer John Dunlop (PA)

First and foremost, a potential Triple Crown notwithstanding, it is imperative to remind everyone that success in the Ladbrokes St Leger would confer a still greater distinction upon his trainer than upon Camelot himself.

Over the years, 15 colts have added the oldest Classic to the 2,000 Guineas and Derby, albeit three during the First World War ran over tracks that did not demand anything like the same versatility.

But Aidan O'Brien would have no precedent if completing a clean sweep of all five British Classics in one season. That achievement eluded even his namesake, and predecessor at Ballydoyle, Vincent O'Brien, who produced the last colt to win the Triple Crown, Nijinsky, 42 years ago.

Only two have been eligible to try in the meantime, and both were deemed to have better priorities. So the very fact that Camelot is running at Doncaster should perhaps be celebrated every bit as much as the ability presumed to separate him from his rivals.

Both Nashwan, in 1989, and Sea The Stars, three years ago, sat out the third leg after winning the Guineas over a mile, and the Derby over a mile and a half. An increasing obsession with speed, among commercial breeders, had tainted a race that makes unsparing demands of a barely mature physique – taking the runners fully 572 yards beyond the Derby distance, down that endless straight at Town Moor. But John Magnier and his partners at Coolmore Stud wield immense influence over the bloodstock market, and their success with middle- distance champions in Montjeu and Galileo has emboldened them that their latest paragon will not be demeaned – as if any champion could be – by matching the speed of a miler with the stamina, heart and durability demanded by the Leger.

It is worth reiterating that Oh So Sharp won the 1985 running, after taking the 1,000 Guineas and Oaks against her own sex. As colts, however, both Nashwan and Sea The Stars kept the Prix de l'Arc de Triomphe at the top of their autumn agenda – and Nijinsky's defeat in that race had been notoriously blamed upon his recent exertions at Doncaster. But Nijinsky had pursued a more exacting summer schedule than Camelot, who will duly retain every right to proceed to Longchamp if all goes well today.

Yet it would be disrespectful, both to the race and his rivals, to suggest that the favourite could be any kind of sensible investment at such microscopic odds. Admittedly, he seems to tower above a fairly modest crop of three-year-olds. It has long been surmised that Camelot crossed the biggest barrier to a Triple Crown when he won the Guineas, and he certainly proved a class apart when stepped up in distance at Epsom. While he proved nothing like so dazzling in his home Derby, conditions were grim and he was probably ready for a break.

It is fascinating, however, to hear O'Brien nervously pondering the physical change in Camelot since. "His body is [now] more like a miler, in that he is round and strong, as opposed to angular and lean," he says. "That is a little thing that would be in your mind."

On pedigree, equally, Camelot's stamina could not be considered absolutely copper-bottomed today. Montjeu, his late sire, has produced many very strong stayers but his dam, Tarfah, is a daughter of the speed influence, Kingmambo, and showed tremendous dash during her own career.

Sure enough, the man who has won the last two runnings has declared a pacemaker to leave the favourite no hiding place. John Gosden is under no illusions about the task facing Thought Worthy and Michelangelo, but is rightly determined to make a race of it. "We want a Triple Crown, not a hollow crown," he said yesterday, with reliable felicity.

His stable jockey, William Buick, perseveres with Thought Worthy after artfully giving the slip to Main Sequence, the Epsom runner-up, in a slowly run trial at York. Apart from Camelot himself, that qualified Thought Worthy as the only Derby runner to have won a race since, but Main Sequence closed to a neck and might yet outrun a pedigree that had suggested him a very questionable stayer. It is possible, however, that Encke could reverse form with them both, having plodded on for third. Though himself a son of Kingmambo, his stout maternal pedigree entitles him to prove a different proposition for this kind of test and could make the frame at big odds.

As Mickael Barzalona retains the mount on Encke, Frankie Dettori is free to ride Michelangelo for Gosden and it is this unexposed son of Galileo who offers the best each-way value (at 12-1) for those who find the odds about the likeliest winner unpalatable. Michelangelo has only had four starts, two over a course he dislikes, and has been freshened up for a track and trip that should be right up his street.

Gosden saddled a smart prospect on yesterday's card, in Ashdan, though top billing went to John Dunlop for winning the Stobart Doncaster Cup with Times Up, a day after announcing his intention to retire at the end of the season. Ashdan's owner, Khaled Abdulla, also appears to have a young colt going places out today in Dundonnell (2.25). Rex Imperator, the latter's stablemate, is tempting in the big sprint but Steps (3.0) no less so at twice the price.

Dawn Approach, meanwhile, makes his first start in Godolphin silks, if still in the care of Jim Bolger, when essaying a first Group One success at the Curragh this evening. Certify just held on to her own unbeaten record for Godolphin yesterday, in the Barrett Steel May Hill Stakes, and the stable will have high hopes that Farhh can see off just three rivals for the Prix du Moulin at Longchamp tomorrow. The three big local Arc trials are staged on the same card, notably one featuring the Japanese raider, Orfevre. By then, however, Camelot should already have promised to exorcise Nijinsky's Parisian curse on the Leger.

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