All-Ireland SF Qualifier/Tyrone v Galway: The Bank of Ireland All-Ireland football qualifiers are about to get interesting. This afternoon at Croke Park brings one of those defining matches that have become part of the football calendar at this time of the year.

Tyrone and Galway both lost their provincial titles at the semi-final stage last month and have entered the qualifier series with tails between their legs.

Those defeats to Donegal and Mayo, respectively, weren't totally unexpected, but deepened the pessimism surrounding the teams in the preceding weeks. That mood would have been inexplicable to those who watched the sides contest an enthralling National League semi-final and replay back in April, at the end of which Galway had won, but only after two periods of extra-time. This also suggested that the counties had discovered their appetite in time for the summer.

Since then, it's been largely downhill. Tyrone did have an impressively comprehensive win over Derry in the Ulster preliminary round, but the display against a weakened Fermanagh was unconvincing, whereas there was no response when Donegal came at them (an outcome made worse by Donegal's inability to cope with Armagh's power play last weekend).

At least Tyrone had the excuse of being All-Ireland champions, a status that hasn't survived more than 12 months for 14 years. Galway have no such alibi, the team having under-performed in both of the championships since last winning the All-Ireland in 2001.

But since the hard-won defeat of Tyrone in the spring, John O'Mahony's team have frustratingly lost the final after letting Kerry get too far ahead, sustained the loss of both experienced wing back Seán de Paor and his understudy Kevin Brady and been badly beaten by Mayo.

Tyrone will be viewed as being in slightly better nick because their second half against Down in the qualifier two weeks ago was a more impressive evening's work than Galway managed in putting away Louth.

But there is a view in the county that the team, while maybe improving, has few realistic prospects of retaining the All-Ireland and on that basis the sooner they get beaten in the qualifiers, especially before playing Armagh, the better in order to let the players put their feet up, rest and be ready for next year.

Mickey Harte, whose patiently determined philosophy of winning every match as it came last year was so integral to the All-Ireland win, is unlikely to subscribe to the healing powers of defeat but the desire to draw a line under the year to date must be strong.

For Harte there has been the disappointment of seeing the All-Ireland defence hitting turbulence when many believed that his more varied training regime might prove to be the alchemist's stone that would allow the side to keep going year in, year out without any loss of edge.

Almost symbolically, trainer Paddy Tally - an enthusiastic participant in his own drills - broke his leg in a club match a couple of weeks ago.

Nonetheless the year has been well handled in most respects. The cup has been brought around in an orderly fashion and collateral social damage has been limited for a county winning a first All-Ireland with relatively small slippage in terms of commitment.

But there are factors over which no management has any control. Eamonn Coleman, who managed Derry to the 1993 All-Ireland, told Joe Kernan last year that the greatest obstacles to successfully defending the title were injuries cropping up unexpectedly. Tyrone have had their share of those with Peter Canavan's rehabilitation taking longer than expected and being disrupted by further injury.

But it was the sudden death of captain Cormac McAnallen that has dominated the year since last September's historic victory.

Former Tyrone manager Art McRory makes this point about keeping players focused: "The attitude of a team is determined by the attitude of the better players. Peter Canavan is so committed and driven that he sets the tone for the whole panel. Cormac was another of those personalities."

A high-profile player, who was recognised as the leader of his footballing generation, he inspired team-mates even at training. His loss has also effectively robbed the defence of two players, his own imperturbably steadying influence at full back and that of his replacement Conor Gormley at wing back.

Small wonder that Harte dismissed any suggestion that the NFL semi-final had drained the team by saying that, after all they had been through over the past few months, he didn't think that a league match would have had much impact on his players.

But sometimes events take on a significance of their own. Whether they intended to be or not, both sides became revved up for the match and its replay. It's possible Tyrone were over-committing at the wrong time of the year. A settled team after all doesn't need the momentum that the league can give a developing side.

Galway were looking to rediscover momentum and did but the final turned out to be a major disappointment, another failure to beat Kerry (the fourth at Croke Park during O'Mahony's tenure) and another defeat at Croke Park where Galway haven't won since the 2001 All-Ireland final.

They have had their own troubles. A plague of injuries in the half backs (six out at various stages) meant that Paul Clancy became the team's centre back and is currently only half run in to the position, whereas captain de Paor is out for the season together with Brady.

Declan Meehan is the new captain but, after a couple of years as the best footballer in the county and a staggeringly good campaign with Caltra winning the All-Ireland club title, there are signs of fatigue, as often happens with players who have been on the go with the club until the spring stages.

There will be speculation about John O'Mahony's future should Galway lose.

Now in his seventh year he may feel, in the event of defeat this afternoon, that he has brought as much to the county as he can.

But he has the comfort of having been through this before in 2001. Prior to that match it was speculated that defeat for either Galway or Armagh would probably bring the curtain down on the losing management team.

So it proved for Brian Canavan and Brian McAlinden.

O'Mahony can draw further encouragement from the striking parallels between this and three years ago.

Galway were also defeated in the league final, beaten surprisingly in the Connacht semi-final, rehabilitated by a largely undemanding match in Leinster and then drawn against the previous year's Ulster champions at Croke Park.

Back then Tomás Mannion was reinvented as a reconditioned centre back just as Clancy has been this season.

It may be that Galway are finding it hard to get excited by the Connacht championship any more. Winning the province has neither given the team much momentum nor a morale boost in the past two years. At this stage there is a suspicion that the players need an outside challenge to intensify motivation.

This weekend they have it.