Even at the death, Mark Lynch was performing miracles for this Derry team – yet ultimately it was not enough.
This was a game that screamed danger for Derry.
Minus their first-choice midfield and their inside forward line, a slew of club fixtures squeezed in after their Ulster Championship defeat to Donegal pared their panel down even further.
The record books also spoke of defeats to Longford away in 2006 and 2012.
Relegation to Division Four for the visitors in the spring, along with the home side's appearance in the National League final, was surely the rationale for the 15/2 odds against a midlanders win.
Yet Derry's defending was their undoing.
"We tried to correct it by dropping Gerard O'Kane back," explained manager Brian McIver afterwards.
"Barden and Kavanagh gave us serious trouble in their inside line and McGee gave us serious trouble out the field.
"But we know in these back-door games, you have to play out of your skin and to be fair to Longford they did that. I thought over the course of the game we didn't play nearly as well to win it."
Although he named those that were out of the game through injury: "Dermot McBride, Emmet McGuckin, Patsy Bradley, Carlus McWilliams, Benny Heron. Ryan Bell got hurt there against Newbridge ... ", he felt the loss was their own fault.
"We have no excuses however," he stated.
"We had enough good players on the field to win the match and we just didn't manage to do it.
"I wouldn't put it down to application, a lot of times I thought our decision-making on the ball was very, very poor. Such as the number of turnovers we had in the first half, carrying ball into tackles, kicking ball away.
"Maybe a lot of changes from the last day affected us but we have no excuses. We are the Division One side but they played like a Division One side."
Playing with a 1-1-1 attacking formation of Francis McGee, Paul Barden and Brian Kavanagh, Longford grew in confidence throughout the first half as their blanket defence demoralised Derry, as Donegal's had almost a month back.
Barden took his third goal chance on the half-hour to draw level and from that point, Longford remained largely in control, with Michael Quinn colossal in sniping supporting runs.
Derry managed to draw level with six minutes remaining through a Lynch piledriver of a goal, but Longford replied instantly with a goal of their own from Mark Hughes, and held Derry at arm's length for the final stages.
Derry have been blessed under Brian McIver, with all their six Championship games coming with the marginal gain of home advantage. However, they have only won two of them.
A major stumbling block for them seems to be coming up against the blanket defence. Longford manager Jack Sheedy had his side create a rudimentary blanket after what he had previously witnessed.
"I watched the Donegal game live on TV, never thinking we'd be coming to Celtic Park for this one, but we felt that if we could get them on the counter, it would give us an opportunity," he said afterwards.
"You saw Michael Quinn, what he did with the ball going forward, and that was experience, that was what we worked on on the training pitch over the last couple of weeks."
Still, the day gave us one of those rich, sun-kissed evenings when it means everything to small supports travelling out of loyalty rather than expectation.
There was a lot of raw emotion on that pitch afterwards that reflects that no matter how many muse on the possibility of tiered Championships, there will always be an appetite for a giant-killing.
"(It's a) massive result," continued Sheedy.
"It's easy to say when you've come out the right side of the game but we knew we were capable of a performance like that."
DERRY: T Mallon; O Duffy, C McKaigue, A McAlynn; G McKinless, M Craig, SL McGoldrick 0-1; M Lynch 1-4, 2f, K Johnston; A Devlin, E Bradley, E Lynn 0-2; J Kielt 0-4, 1f, T O'Brien 0-2, C McFaul. Subs: G O'Kane for McAlynn, BC, 14m, B Heron 1-1, 0-1x'45') for Duffy 24m, N Holly for E Bradley (HT), D McKinless for Devlin 41m
Yellow cards: McFaul 43m, Craig 61m
Black cards: McAlynn 14m
Red cards: 0
LONGFORD: D Sheridan; D Brady, B Gilleran 0-1, F Battrim; C Smyth 0-1, E Williams, S Mulligan 0-1; B O'Farrell, K Diffley; M Quinn 0-2, F McGee 0-2, P Barden 1-2; A Rowan, B Kavanagh 0-3, 1f, S McCormack 0-4, 2f. Subs: M Hughes 1-0 for Rowan, 61m, N Mulligan for Smyth 64m
Yellow cards: Kavanagh 11m
Black cards: 0 Red cards: 0
Referee: M Higgins (Fermanagh).
Monaghan girls in pole position to retain title
The Ulster ladies championship series is taking shape following weekend wins for Armagh, Monaghan and Fermanagh.
Ulster ladies senior championship holders Monaghan moved through the gears to see off Cavan and book their ticket in another title decider.
All-Ireland intermediate winners Cavan dipped their toes into the senior championship pool at Crossmaglen, but found Monaghan holding too many aces on this occasion.
The Oriel girls recorded a convincing 5-14 to 1-5 victory but took time to find their stride, despite leading by 3-5 to 1-4 midway through. Brave Cavan kept trying but the Breffni girls could only add one second half score as Monaghan pushed on.
Cathriona McConnell sent over seven points for the winners, whose experience shone through as play progressed against their newly-promoted opponents. Cavan can bounce back, though, in the second phase of championship games to come.
Donegal took on Armagh in the second senior semi-final with the Orchard girls aiming to build on a quarter-final win over Tyrone. Donegal, though, were keen to step up to the mark and an exciting tussle ensued.
The Donegal girls showed ahead at half-time by 1-5 to 0-7 but Caroline O'Hanlon, Mags McAlinden and company rallied to the Orchard cause as they came through to win in the end 1-15 to 1-9. They now meet Monaghan in the Ulster final.
Fermanagh are through to the Ulster intermediate final after overcoming the spirited challenge of Antrim at Crossmaglen (5-10 to 3-9).
The Saffron girls gave a good account of themselves but Caroline Little and the Erne side just packed that bit more firepower on the day.