Sideline Cut: For reasons too convoluted to go into, a group of us exited Croke Park last Sunday night through the Hogan Stand tunnel where the teams run out and we walked across the field to the Cusack Stand to where the last of the catering staff were washing down the counters.

In the darkness, we took in the view and scale that would have confronted the footballers earlier in the afternoon. Unlit and empty, with one or two forlorn bulbs shining from the depths of the corporate section, it was hard to believe the stadium had been bursting at the seams just hours earlier. With so much space and quietness, it was difficult to remember that at mid-afternoon, all of Irish life revolved around this theatre. It felt like a place abandoned. But then, in a way, it had been.

It is sad Mayo's latest All-Ireland final torment will always be recalled by the image of great numbers of the team's fans fleeing Croke Park, unable or unwilling to watch the concluding scenes of what was a demoralising September Sunday. Given Mayo's unhappy history of mass emigration this particular leaving of the county had a sharp metaphorical edge to it, except this time it was wilful. Some of those were undoubtedly leaving not just the team and the game and an All-Ireland final that had been embraced as a Godsend but also Mayo and Ireland to return to their lives in the fast and unsentimental cities of the New World.

Of all the recent All-Ireland finals, there was a romantic attachment to Sunday's based on Mayo's epic wait for the day when its football team would be crowned the best in Ireland. That Kerry, the standard bearers of the game, were the opposition just whetted the appetite for what could have been a great day of sport.

As was handsomely and rightly noted, Kerry played tough and direct and at times beautiful football and inflicted a lesson on Mayo, made them look like pretenders. Afterwards, they were pleased and gracious and high-tailed it off to Tralee, champions for the 33rd time.

But Kerry's class and strength only partly accounts for Mayo's experience. Mayo's day was dark and troubling in a way that is not confined to the immediate disappointment of losing a match. In every All-Ireland final, a county loses a match. This was something more. Why it went wrong is for another day and is something the Mayo team and their supporters will ponder over the winter.

The element of the day that lingers, however, is not tactics or the non-performance of several of Mayo's players but rather the inconsolable departing the stands. It was that really awful sight of hundreds and finally thousands of Mayo people unwilling or unable to stay with their team after it became apparent that despite the promises and pledges of a fine summer of football, they would not be delivering, not this year. They walked away in a hurry, like visionaries who suddenly realised the apparition was a fake.

In almost all games, you will find one or two supporters leaving early. And on All-Ireland final like Sunday's, there will always be a small minority who feel compelled to get out, driven by disgust or hurt or just the practical imperative of beating the traffic or getting a decent seat in Harry's of Kinnegad.

But what began as a trickle after around 48 minutes on Sunday quickly became, in the truest sense, a movement. Given most of the All-Ireland football finals of the last decade - with the notable exception of Galway v Meath in 2001 - have been tight and compelling encounters, the one-sided nature of Sunday's game was always going to deflate the atmosphere.

But sitting in Croke Park as the crowd drained away was eerie. It was as if those that left early were making their own statement. It wasn't so much resignation as a protestation. And it was wrong. As one Mayo man - who stayed to the laughably dull end - remarked, "did their tickets read, 'Mayo guaranteed the Sam'?" The Mayo players and management have no option but to conclude that as a unit, they erred terribly on what may have been this team's best crack at an All-Ireland title (because, given the perilous nature of championship, it may have been their only crack). Mystifyingly and fatally, they asked no questions of Kerry.

They allowed the lords of the dance to own the floor from the beginning, allowed them to look better than they probably are. Whipped as Mayo were, they scored 2-9, missed a couple of goal chances and were beaten by eight points. Their main failure was they never caused Kerry to doubt. They needed to play, as the saying goes, like men possessed. Instead they resembled men haunted.

It must have been a fairly sickening experience having to run and jump and kick a football in the last 10 minutes of an All-Ireland football final that has shocked you. They must have been vaguely aware of how dramatically the stands emptied out. How must that have made them feel? That their own county folk were ashamed of them? Because that was the sense you got. There was an embarrassed quiet around Croke Park last Sunday.

Even for Kerry fans, the occasion must have been diminished by the relative absence of dramatic and sporting tension.

As All-Irelands go, there was a sense of accomplishment rather than euphoria after this one. After the adventure and charisma provided by teams like Fermanagh and Wexford and Westmeath, it was somewhat sobering for the public to see Kerry brand their own formidable insignia on the summer of football when all was said and done. The more things change, the more they stay the same. The ease with which Kerry returned to the top of the game and averted yet another crisis of form suggested that for most counties, the dream will always be an illusion and that effort and sacrifice will only take a team so far.

If the next few All-Irelands are divided out between the superpowers of the modern game, perhaps we will see Croke Park emptying out more often. Perhaps the county teams who are putting themselves through rigorous regimes just to live with the big teams will become demoralised and despair of doing anything other than fleetingly challenging the old order. Perhaps the day will come when they lose heart and interest.

Because the one thing the last 10 minutes of Sunday's All-Ireland final hammered home was that the popular movement that has enriched Gaelic football remains evanescent. Just because the people are coming this year and next year does not mean it will always be so. Croke Park will not always be chic or hip: some day it will again look dated. The romance of the qualifiers can only appeal for so long.

For the past few years, football has captured a terrific audience. The trick now is to keep them spellbound and that is not going to be easy.

The strangeness of experiencing Croke Park in the last 10 minutes of the season might have been a harbinger for some future time when maybe, just maybe, the All-Ireland final will not play out in front of a packed house. Perhaps the saying, so commonplace last week, that an All-Ireland victory for a county like Mayo would "do the game good" is a tacit acknowledgement of that bleak scenario.

Easy to fault as the Mayo football team were on Sunday, it could still be argued those who bailed out when the going got uncomfortable do not deserve the team.

Mayo fans are lucky: they have a team with enough talent to plausibly make it back to an All-Ireland final again. They might win it in the next three years. Or they might suffer another really bad and scarring day. Either way, their players should never have to walk alone.