LAST August, they delivered the lowest-scoring All-Ireland semi-final for 55 years in a dour, security-driven contest. On Saturday night, they switched to expansive mode and provided a highly entertaining game for the Croke Park audience of 23,855.
The background to the contrast rested on a changed approach, especially by Donegal, who had, as Dublin manager Pat Gilroy described it, "a different defensive structure tonight".
Donegal kept far fewer players behind the ball than they did last August and they also kicked long more often. Dublin mixed it up intelligently, too, so the end product was good to watch, especially in the second half when the momentum alternated with an exciting rhythm.
The result looks stark and cold from a Donegal perspective, showing a nine-point defeat while conceding 2-16 for the second time in three games.
However, there was no comparison between their performance against Kerry two weeks earlier and Saturday night's effort, which sustained itself with real purpose right up to the closing minutes.
Donegal trailed by three points as the game headed into stoppage-time and, having clung tenaciously to Dublin's coat tails all evening, they would have hoped for a late break which might rescue a point. However, it was Dublin who went into blitz mode as Bryan Cullen and Diarmuid Connolly hit goals in the 71st and 72nd minutes respectively.
"We fatigued a bit in the last five or 10 minutes. I don't think our fitness is at the same level as Dublin's, but it was still disappointing to concede two late goals," said Donegal manager Jim McGuinness.
As Donegal prepared for the long journey home, the question of what might have happened if Michael Murphy had stayed on the pitch would have dominated their thoughts. Murphy was thoroughly enjoying himself on a crisp, spring night until he injured his knee midway through the second half.
He tried to play his way through the pain but eventually had to succumb in the 59th minute, at which stage Donegal were trailing by two points. Murphy had played a substantial role in Donegal's best period, which came in the opening 10 minutes of the second half, during which they wiped out Dublin's four-point interval lead (0-9 to 0-5) to draw level.
It was level again after 55 minutes (0-11 each) before Dublin kicked four points in a surge that Donegal couldn't counteract. Murphy's departure greatly reduced their attacking threat, leaving McGuinness to rue the loss of a man who might have made the crucial difference.
"At that stage (when Murphy got injured), we were going well. Everybody was on the same wavelength, we were pushing on and there was a good momentum to our game," he said.
Dublin weren't short of impetus either -- indeed their capacity to power it up as required characterised a performance in which the confidence that comes from being All-Ireland champions was hugely significant.
Attackers Kevin McManamon, Connolly and Cullen, midfielders Michael Darragh Macauley and Eamon Fennell and defenders Rory O'Carroll, Philly McMahon and Cian O'Sullivan were all on their game, playing with commendable self-belief while backing themselves all the time.
Dublin lost Ger Brennan (sickness) and Alan Brogan (twinge) in the first half, absences that they could argue were as significant as Murphy's departure for Donegal, but they were well able to compensate through a strong back-up cast.
Subs Dean Rock, Dean Kelly and Craig Dias all made important contributions, which will have further pleased Gilroy as he attempts to broaden the squad base ahead of the championship.
Dublin's defeat six days earlier was attributed to a lack of real intensity, which allowed Down to take the initiative, but that never looked like being repeated on Saturday.
Dublin set the agenda from the start, with Cullen scoring after 20 seconds, followed by points from Connolly (free) and John Cooper, who timed his raid to perfection from the half-back line.
By half-time, eight different Dublin players had scored (it increased by another four in the second half) and while Donegal had settled well after the early setbacks, they were somewhat fortunate to be only four points adrift as their goalkeeper Paul Durcan had made three excellent saves.
The contrast between this game and the All-Ireland semi-final was underlined by the half-time total (14 points) -- the same as the final tally last August.
The win moved Dublin comfortably into the semi-final zone (they play Mayo and Cork in their final two games) while Donegal are facing a relegation scrap with Armagh on Sunday week.
McGuinness mentioned Dublin's ability to alternate their approach as a key ingredient in their success. "They kick the ball a lot but when they don't kick it, they go at you really aggressively. It's a good mixture. We're disappointed how tonight went but we'll take a lot of positives from it too," he said.
Dublin will take even more as they were without five of their All-Ireland final starting line-up, yet scored 2-16 against an opposition that restricted them to 0-8 seven months earlier.
"I suppose the result flattered us in the end with those two goals. Donegal really put it up to us in the second half. We gave them that opportunity with a lot of mistakes, giving the ball away even when we weren't under real pressure. But, overall, it was a good game to win," said Gilroy.
He will certainly be pleased with the range of scorers and with the general application levels. Donegal will be encouraged by the third-quarter cohesion that enabled them to out-score Dublin by 0-6 to 0-2, but they couldn't sustain it.
A nine-point defeat wasn't a fair reflection of their efforts but Division 1 is a tough environment where even small mistakes get punished severely -- as Donegal discovered when they conceded those two late goals, which -- as well as killing the game off -- seriously damaged their scoring difference.
Man of the Match: M Murphy (Donegal)
Scorers -- Dublin: D Connolly 1-3 (0-2f), B Cullen 1-1, K McManamon 0-3, J Cooper, A Brogan, MD Macauley, E Fennell, T Quinn, D Kelly, S Cluxton (1f), P Flynn, D Rock 0-1 each. Donegal: M Murphy 0-6 (3f, 1 '45'), A Thompson, L McLoone, N McGee, P McBrearty (1f), C Toye, D Walsh, M McElhinney 0-1 each.
Dublin -- S Cluxton 7; C O'Sullivan 7, R O'Carroll 8, P McMahon 7; J Cooper 7, G Brennan 6, K Nolan 7; E Fennell 7, MD Macauley 8; B Cullen 8, A Brogan 6, P Flynn 7; T Quinn 7, D Connolly 8, K McManamon 8. Subs: S Murray 6 for Brennan (24), D Rock 7 for Brogan (30), D Kelly 7 for Quinn (h-t), C Dias 7 for Cooper (59).
Donegal -- P Durcan 8; F McGlynn 6, N McGee 7, P McGrath 6; A Thompson 7, K Lacey 7, L McLoone 7; C Toye 7, N Gallagher 7; M O'Reilly 5, R Bradley 7, M McHugh 6; P McBrearty 6, M Murphy 9, M McElhinney 6. Subs: D Walsh 5 for O'Reilly (30), E McGee 6 for Toye (53), A Hanlon 5 for Murphy (59), D McLaughlin for Bradley (64).
Ref -- E Kinsella (Laois).