Just as we imagined Kerry to be applying a last coat of varnish, Dublin surged to the Hill with scarcely credible tidings. This was their field, their day. So they met the Kingdom's victory dance with a round of buckshot and everything we thought we knew about hierarchy and lineage suddenly felt counterfeit. For Dublin's total fidelity to a workers' constitution induced palpable despondency in Kerry.
To win the closing seven minutes 1-3 to 0-1, the Dubs simply went to a place that maybe no old team could have access to.
They reclaimed Sam with a game plan so rigid, so non-negotiable, Pat Gilroy might as well have presented it to them leather-bound and stamped with gold lettering. The team in blue was insatiable, playing as if defeat might curse them all the way to senility.
And it felt less a team stretching for home in the end than a whole city reaching out to the glamours of its past.
In doing so, Dublin persuaded Kerry to all but abandon theirs. Jack O'Connor's team began fouling. Sporadically at first but, the clouds in their heads darkening, almost slavishly as the clock began to race. They panicked. Imagine. The world had been under an illusion that they wouldn't recognise the condition, let alone seek it out for refuge.
But industry made them forget themselves. The perfect articulation of Gilroy's creed.
When he took charge of Dublin, he understood there was no future in them trying to live a romantic existence while there was still breath in those silver-tongued rogues down south. The Dubs' best hope was to be dry and dull and maybe a little militaristic about their football.
So he decommissioned the notion that Sam Maguire might be accessible through wall-mottos and proverbs and phoney little shows of faux unity in front of an impatient Hill. For Dublin to win they, first, had to learn how not to lose.
Yesterday, they set the terms of engagement in a way that Kerry tried to rise above, but couldn't. By the mid-point, the Kingdom had claimed just three scores, albeit one of them was a drop-dead-gorgeous 'Gooch' Cooper goal set up by the mesmeric Darran O'Sullivan.
This just wasn't the game O'Connor's men had come to play.
Dublin's half-forwards hunted with dervish energy between their own midfield and half-backs and only two of their full-forward line showed an interest in hanging close to Brendan Kealy's goal. This was about the siphoning of traffic into areas where it suited Dublin to have numbers.
And yet, being honest, Kerry looked to have done enough to win. Their initial positioning of Kieran Donaghy at wing-forward was smart and, palpably, discomfited the city boys. And if Paul Galvin's 24th-minute arrival was almost certainly earlier than O'Connor might have planned, the Finuge man's presence clearly made Kerry a more coherent team.
It should be said too that Ger Brennan was lucky to escape a red card when his high elbow temporarily took out Declan O'Sullivan early in the second half. But, between the 54th and 63rd minutes, Kerry kicked four unanswered points that in a game of this intensity bore the feel of an epic harvest.
And it was the beginning of the end for them.
Immediately after Gooch had kicked the fourth, Declan O'Sullivan gave possession away to Cian O'Sullivan and, two passes later, Kevin McManamon was goaling in front of the Hill. Croker shook as if the sky itself was coming down. Which, to some degree, it was.
McManamon's goal changed everything. Suddenly, the younger, hungrier team was ardent and believing. The older, careworn side looked weighed down by time.
It wouldn't have happened in Dublin's previous life. Their old way was to throw a pair of dice on the table and hope for sixes. They used devour Leinster with football so free-flowing and open it left their supporters bloated with conceit. Then some big gun from Ulster or Munster would hunt them down like crims guilty of a parole violation and the grief and disbelief always made for interminable winters.
Dublin couldn't defend. Gilroy knew that every season would be another bounced cheque until he addressed the fact.
Remember his first Leinster Championship game? The half-time score? It read Wexford 0-8; Dublin 0-2. The Hill howled like a pen of angry coyotes. Dublin recovered to scrape a win but, soon, Meath belittled them with five goals. Gilroy was, palpably, on probation.
But progress came in gentle increments and the team that stands today at the summit of football will never be mistaken for Globetrotters with a Harlem twang. They hit hard and, on occasion, without reference to much scruple. They take liberties. Some of their fouling is, patently, strategic. They know when and where it pays to sin.
Bryan Sheehan's first kickable free yesterday arrived after 34 minutes. It was just about within his range and, though the kick dropped short, Galvin managed to snaffle a point.
But Dublin were being incredibly disciplined about where to draw sanction from Joe McQuillan. There were zones to foul in and zones to simply fill with bodies. It wasn't beautiful, but it was undeniably smart.
Kerry weren't exactly indifferent to the dark arts either and, if the game lacked the counterbalance of grace, it more than compensated with the sheer depth of its intensity. When McManamon's goal was followed, quick as drumbeats, by points from Kevin Nolan and Bernard Brogan, Dublin seemed to have it won.
But then Donaghy's impossibly audacious 70th-minute altitude score looked to have secured the GAA an extraordinary autumn windfall. The escape to a replay would have gone down as a typically Kerry signature on the epoch. Cool heads and calm hearts pulling it from the fire.
Only thing was they weren't cool and they weren't calm. If anything, Kerry had begun to over-heat.
In the brewing maelstrom, Dublin's adherence to structure and shape and a code of selflessness in respect of the collective, now gave them an unstoppable, machine-like form. They swept forward in a stern, blue wave and the wonderful McManamon drew a free from Barry John Keane.
Bernard Brogan reached down to hug the St Jude's man, then invited his goalkeeper to join them. Stephen Cluxton came ambling up like a defendant reluctant to enter the courthouse early. McQuillan told him to hurry, at which stage he kindly broke into a pall-bearer's stroll.
The earth itself seemed to whistle as Cluxton lined up the kick. He nailed it, the whole place suddenly convulsing. Dublin's field. Their day.
Gilroy's worker's constitution all but carved in stone.