How the game unfolded
Niall Scully's omission has spread through the city's watering holes like wildfire over the previous 18 hours but it is not his exclusion which is the shock, but his replacement.
While Mayo's Paul Durcan switch was widely expected, Dublin opt to introduce Eoghan O'Gara, not Diarmuid Connolly, nor Paul Flynn, nor indeed Cormac Costello.
Unusually, Dublin win the toss but, instead of opting to end the game with the expected aid of the emotionally magnetising Hill, they chose not to. If it seems to set a pattern, then one forgets that this is Dublin v Mayo, for which there is no pattern at all.
Dublin 0-0 Mayo 0-0
Con O'Callaghan calms early nerves with the pre-emptive strike so many Mayo supporters may have feared; Ciaran Kilkenny fends off Lee Keegan to pave the way for the Young Footballer of the Year to finish, with more than an indulgent step or three, a wonderfully decisive goal.
Dublin 1-0 Mayo 0-0
The goal has not settled Dublin but rather settled Mayo; Andy Moran and Donal Vaughan raise white flags but of even more significance, Jack McCaffrey clatters into Colm Boyle and damages his knee.
In vain, he tries to shake the pain but the 2015 Footballer of the Year, who watched last year's final from the bleachers, departs before the 10th minute. A scuffed Dean Rock free precedes a McLaughlin point. Not for the first time, the sides are tied.
Dublin 1-0 Mayo 0-3
Mayo are dictating the terms of engagement; Dublin can find neither tempo nor temperature; Kilkenny is being kidnapped by Lee Keegan and the O'Gara gambit has failed.
Mayo lead for the first time in the 20th minute when Moran scores once more from a calamitous Dublin kick-out; it is a fraught day for Stephen Cluxton off the tee.
Forwards coach Jason Sherlock races on to consult with Cluxton but the trend is unbroken; Mayo score seven points from play, with five different scorers, but they also kick five poor wides.
John Small and Rock chip in with crucial points from confident play; Rock has rebounded well from a difficult start and his free on the stroke of half-time leaves the minimum between them.
Dublin 1-5 Mayo 0-9
Dublin have admitted that their first-half approach has faltered and withdraw not merely O'Gara, but Paddy Andrews too; the arrivals of Connolly and Kevin McManamon affirm a switch in emphasis to more carrying and running.
Mayo stay off the field for 19 minutes at the break - four longer than officially permissible - Aidan O'Shea loses the first throw-up ball, his first in many, many years (it seems) and Paul Mannion scores an instant leveller before McManamon inches Dublin ahead.
Dublin 1-8 Mayo 0-10
The anarchy that fatally attracts itself to this fixtures arrives in a whirlwind. Two goal chances; two dismissals.
Cluxton saves spectacularly, at point-blank range, when Jason Doherty is put clean through by Moran after another Seamie O'Shea midfield success.
Then Mannion escapes Brendan Harrison's clutches but, instead of playing O'Callaghan in for a certain goal, goes himself but is denied by David Clarke.
Then Small, standing sentinel as Boyle charges through the middle, juts an offending shoulder; as the players jostle in collective outrage, Donal Vaughan delivers the idiotic forearm smash on Small that also curtails his afternoon.
Dublin brim, momentarily, with confidence, necklacing their best few moments of attacking play in the game, as Brian Fenton's point gives them a two-point lead, their biggest since their opening goal.
Dublin 1-10 Mayo 0-11
Just as it seems Dublin are approaching the moment of most authority and control, Mayo unleash chaos.
Tom Parsons hives another kick-out in midfield and feeds Aidan O'Shea before Cillian O'Connor and Moran combine for a spectacular Keegan goal that rouses their hungry, desperate support.
Kevin McLoughlin tags on a lovely left-footer before Rock levels the game for an eighth time.
Moran's wide - his side's eighth - hints at anxiety - but a soaring point from play and a free from O'Connor restore Mayo's lead - at two points, the biggest it has been in this half.
Dublin 1-13 Mayo 1-15
As Dublin draft in Bernard Brogan, Mayo are leaking experience: none of Moran, Boyle, McLoughlin or Keith Higgins finish the match.
Mannion, so impressive for Dublin, notches a fine individual score before the now pressurised Mayo kick-out allows Fenton to break for Philly McMahon; his pass to James McCarthy - score. Level, once more.
Rock and O'Connor then trade points as normal time elapses.
Dublin 1-16 Mayo 1-16
Diarmuid O'Connor runs hard at Michael Fitzsimons down the left wing; referee Joe McQuillan indicates that the Dublin man has pulled an arm. Cillian O'Connor has a chance, 12 months after his last one, to kick Mayo's frustration into history but, aping his team's slow slide in the final stretch, he snatches at the attempt. This time, he is not shy on the near side but smacks and upright; none of his tiring team-mates respond and Dublin clear; Brogan is blocked seconds later, Connolly skews wide.
Dublin are profligate too until Rock's final free liberates a city manacled by anxiety.
In the last 16 minutes of play, Dublin outscore Mayo 0-4 to 0-1 - Championship moments.
Dublin 1-17 Mayo 1-16