After 18 stellar years in his role as Vincent O'Brien's successor, today is a day with the stark potential to define the current Ballydoyle incumbent's illustrious tenure.
Steering the ship of the single most powerful racing and breeding operation in the world is a job of treacherous proportions, and few could have charted the waters quite as skillfully as Aidan O'Brien.
His time at the helm has been one of unsurpassed success, but victory for Camelot in this afternoon's St Leger at Doncaster would ensure a glorious legacy that no one could have anticipated on his first appointment.
The exceptional Triple Crown-seeking colt's unbeaten reign now stands at five, following a trio of Classic victories that displayed the full array of his diverse qualities.
Under a flawless ride from O'Brien's 19-year-old son Joseph in the 2,000 Guineas, Camelot showcased his natural pace and an unlikely turn of foot, before his versatility and stamina came to bear around Epsom's quirky cambers in the Derby.
In heavy ground at the Curragh, his Irish Derby triumph was more workmanlike than spectacular, but that was the order of the day.
Indeed, if there is one attribute that Camelot will need above all others today as he steps into the unknown over a mile and six furlongs, it is that strength of character that he has always shown.
His calm temperament and honest disposition are vital traits that receive little acclaim, but he will need to settle from the off and he is unlikely to get through the day without his tenacity being called upon.
However, we have hitherto seen nothing, either from Camelot or any of his eight rivals from an otherwise sub-standard crop, to suggest that a historic victory will prove elusive. Ursa Major is an intriguing contender for the fledgling Tommy Carmody-Johnny Murtagh partnership, having won with more than a little in hand over this trip at the Curragh last time.
John Gosden's Great Voltigeur winner Thought Worthy is another with solid claims, and it's not insignificant that, as a brother of the stable's 2007 St Leger winner Lucarno, this would have always been a prime target.
For Camelot, the season's final Classic would never have even been countenanced had he not emulated Sea The Stars' superlative 2,000 Guineas-Epsom Derby double of 2009.
In that respect, all involved deserve credit for eschewing the more commercially sensible route in favour of a romantic tilt at legendary status.
And that is what Camelot will suitably claim should he deliver O'Brien a 20th British Classic victory today.
The son of Montjeu would not only be the first horse to replicate what Nijinsky so famously achieved for the Rosegreen handler's predecessor back in 1970, but he would secure O'Brien an even more exalted place in the annals of the game as the first man to complete a Grand Slam of English Classics.
It is, therefore, a daunting duty that falls on the slight shoulders of Joseph O'Brien, but none seem to wear their crown so lightly. The kingdom is theirs for the taking.
Elsewhere on the Park Hill card, Lethal Force appeals as being overpriced to confirm the form of his Newbury triumph over Strong Suit in the Park Stakes. Strong Suit heads the market, but is a horse that always seems to have an excuse for being beaten.
Lethal Force got an easy lead in first-time blinkers when they clashed at Newbury, with Strong Suit flashing home to be denied a neck.
In fairness though, Adam Kirby was excellent on the Clive Cox-trained three-year-old that day and, at up to 11/2, they appeal as an improving partnership that might not be getting due credit.
In the day's featured handicap, the Portland, Face The Problem gets the nod for Jamie Osborne and Kieren Fallon. While a 22-runner five-furlong dash is obviously a minefield from a punting perspective, Face The Problem comes here relatively fresh, his staying-on second at York last week just his third run of the campaign.
Off a 7lb higher mark than when obliging over course and distance on his reappearance last month, he is a value option at up to 12/1.
Best Bet: Lethal Force