Allianz NFL Division 1: Dublin 1-15 Donegal 1-14
Never mind the "only February" caveats. This was a rip-roaring Allianz League contest between All-Ireland kingpins, even in partially experimental form, and ambitious pretenders.
And, quelle surprise, the champions prevailed.
From a position of early trauma, trailing by five points after a flat first 20 minutes, Dublin worked their way back into the contest.
They finally drew level almost on the hour, Colm Basquel wriggling away from two defenders to fire over.
After 65 minutes came the pivotal score: Brian Howard's speculative point attempt dropped in the square where Shaun Patton fatally fumbled and the lurking Paul Mannion, pressurised by Neil McGee, manage to bundle the ball over the line.
Now trailing by three, Donegal battled manfully to the end and scored three of the last four points via a 46-metre Michael Murphy free, Hugh McFadden and sub Paddy McBrearty.
But that sequence was broken up by a 72nd minute point by Dublin full-back David Byrne, showing impressive acceleration so late in the game to break into the scoring zone, and ultimately that proved the match-winner.
Seven minutes of injury-time had been signalled and, after McBrearty had made it a one-point game again, a melee erupted in midfield.
Murphy and his constant shadow, John Small, were both singled out by referee Maurice Deegan for second yellows, ending their night ... and one last chance of a Donegal equaliser disappeared when Daire Ó Baoill overhit a handpass.
And so Dublin hopes of reaching a Division 1 semi-final have been bolstered in pulsating fashion - they now have six points from four games while Donegal, on three, are peering over their shoulders.
Both sides arrived in Croker on the back of weirdly erratic performances a fortnight ago. Dublin had miraculously forced a draw from a position of being nine adrift of Monaghan on the hour.
The following day, Donegal had conspired to fritter away a seven-point lead at home to Galway during the third quarter, ultimately losing by a point.
In a way, then, you could argue that recent history repeated itself. For the second game running, Dublin slumbered out of the Croker traps and paid the price via the concession of an early goal.
In a busy start, Michael Murphy was yellow-carded and then won a free, converted by Ciarán Thompson, before laying on a goal assist in the sixth minute.
It all stemmed from Brian Fenton stumbling as he went to gather an Evan Comerford kickout, resulting on a sideline ball for Donegal. The ball was worked to Murphy, who laid it off smartly to Hugh McFadden on the loop.
The midfielder suddenly found himself with open road in front of him, and he took full advantage, cutting in from the right before planting a low left-footed shot past Comerford.
Four up for the visitors; the hosts reaching for their smelling salts.
Dessie Farrell had plucked Craig Dias from years in the inter-county wilderness and parachuted himself straight into his starting midfield, but the Kilmacud man found the early minutes tough and lost McFadden in the build-up to that goal.
Mind you, Dublin were struggling in many areas of the pitch and, for most of the first half, Donegal kept the five-in-a-row All-Ireland champions at a distance of four and occasionally five points.
In that they were aided by some masterful restarts by Shaun Patton, whose prodigious range and radar frequently located Donegal men in space.
One of those kickouts almost produced a team goal for the ages, too, as Murphy flicked the ball into the path of the marauding Ryan McHugh, who played a one-two with Jamie Brennan only for his shot on goal to be saved by Comerford.
The rebound fell to Brennan, who fisted over to restore a four-point lead in the 20th minute. In the very next move, Brennan then turned away from Mick Fitzsimons and fired over under pressure from Cillian O'Shea (another player promoted by Farrell) to leave the men from the north-west five clear.
However, as the half progressed, Dublin raised the tempo and were rewarded with four of the last five points to leave it 1-6 to 0-7 at the break.
Brian Howard kickstarted Dublin's improvement with a brilliant sidestep inside McFadden and left-footed score. Then, after Michael Langan slotted over at the Hill end, Dublin finished the half with a hat-trick of points from the lively Seán Bugler, a Dean Rock free and Ciarán Kilkenny.
The fun was only starting ... Donegal raced four clear again on the restart, Peadar Mogan settling for point after his first shot on goal was repelled by Comerford.
Then back came Dublin with three on the spin to make it a one-point game.
The game kept oscillating forward and back, with Murphy landing two excellent points from play before a quickfire Fenton brace cut the margin to the minimum once more.
Perhaps the pivotal moment arrived in the 57th minute when Donegal advanced in numbers on the Dublin goal, Eoghan Bán Gallagher playing a one-two Niall O'Donnell before off-loading to McBrearty - but his piledriver was superbly saved by Comerford.
Soon after came Basquel's equaliser, then Mannion's goal, leaving Donegal still chasing their first victory over Dublin since 2014.
SCORERS - Dublin: D Rock 0-4 (3f), P Mannion 1-0, S Bugler 0-2, C Kilkenny 0-2 (1m), B Fenton 0-2, B Howard 0-2, C Costello 0-1, C Basquel 0-1, D Byrne 0-1. Donegal: M Murphy 0-5 (1m, 2f), H McFadden 1-1, J Brennan 0-2, C Thompson 0-2 (1f), P Mogan 0-2, M Langan 0-1, P McBrearty 0-1.
Dublin: E Comerford; D Byrne, J Small, M Fitzsimons; B Howard, C O'Shea, E Murchan; B Fenton, C Dias; N Scully, C Kilkenny, S Bugler; P Mannion, K McManamon, D Rock. Subs: C Costello for Dias (ht), C Basquel for McManamon (54), A Byrne for Bugler (68).
Donegal: S Patton; N McGee, C Ward, EB Gallagher; O McFadden Ferry, R McHugh, P Brennan; H McFadden, M Langan; D Ó Baoill, C Thompson, C McGonigle; P Mogan, M Murphy, J Brennan. Subs: N O'Donnell for P Brennan (46), P McBrearty for McGonigle (52), B McCole for Ward (55), E McHugh for J Brennan (inj 62).
Referee: M Deegan (Laois)