GAA: In advance of the most eagerly awaited football match of the summer to date, it is strange that neither Kerry nor Tyrone have had to face anything approaching the task that awaits them tomorrow.

So no one can be quite sure of either side's credentials going into the Bank of Ireland All-Ireland semi-final.

Neither team met the anticipated big test in their own province, with Cork and Armagh falling at the first hurdle in Munster and Ulster.

Both have impressed going forward but have also had startling lapses of concentration. Furthermore they share a cupboard full of psychological skeletons approaching the season's climax and cut different figures to next week's semi-finalists, the remorseless Armagh and a piratical Donegal already sailing far beyond the seas into which they were supposed to sink.

Tomorrow's teams have different anxieties. Kerry have to win the All-Ireland for the current management team to purge the experiences of being murdered by Meath two years ago and getting touched off by Armagh last September. Anything less and time's up for Páidí Ó Sé and company.

Mickey Harte, in his first season, has a little more latitude, but surprisingly little for a county yet to win an All-Ireland. The current team have disappointed in the face of apparently manageable opposition in the past couple of years and, as Harte keeps emphasising, they have yet to shrug off the questions raised by such misadventures.

The clash of styles between the teams was in full evidence during March's NFL fixture in Killarney. Both show six changes from that day, but there were indications that each found the other's strengths hard to counter. Tyrone's more mobile game caused an amount of trouble, with Seán Cavanagh giving early notice of his running ability at centrefield and Owen Mulligan popping up all over the attack wreaking havoc.

But in the second half Darragh Ó Sé took over at centrefield and won a stream of possession that his team were unable to process into sufficient scores.

There has been a lot of speculation on the likely outcome of the Peter Canavan-Séamus Moynihan duel, but Kerry's training sessions this week suggest that it won't happen. Moynihan played a free role with Tom O'Sullivan and Michael McCarthy staying back in the positions likely to be occupied by Canavan (who was well marked by O'Sullivan in the league) and Mulligan.

This would enable Moynihan to follow Brian Dooher out the field and play a game more to his own liking.

Much was made of Kerry's defensive shortcomings against Roscommon, but it's hard to place too much emphasis on the concession of three goals in a match that was well won at a relatively early stage. The same indulgence doesn't apply to the chances created by Roscommon in the first half that should have resulted in more telling scores than the late blitz.

Tyrone's attack has been more impressive than Kerry's. Whereas the Munster champions have faded in winning positions, their Ulster counterparts have relentlessly scored when on top. In the taut circumstances of the drawn Ulster final, with the title circling the drain, Tyrone came back and retrieved a nine-point deficit.

Kerry captain Michael McCarthy will probably take Mulligan, but the corner back hasn't been in the best of form this year and needs to lift it if he's going to restrain his frequently rampant opponent. Within the county there has been apprehension at Eamonn Fitzmaurice's form, and Tomás Ó Sé was given a spin at centre back during this week's training sessions.

Once again centrefield will be vital for Kerry. Darragh Ó Sé's ball-winning ability is a necessary component of the forward threat because, as Armagh showed last year, there's only so much Colm Cooper and Michael Russell can do without a steady supply.

Eoin Brosnan will probably pick up Kavanagh, and the Dr Croke's player has the mobility and athleticism for the job. But in his short life as a centrefielder he has been more accustomed to going forward than tracking back.

The one surprise in the two selections is the naming of Gavin Devlin for Tyrone immediately on the expiry of a 12-week suspension.

Devlin's leadership qualities as well as his status as the number one centre back have swung the verdict, but three months is a long time to be off the intercounty scene and marking an in-form Dara Ó Cinnéide isn't the ideal way of re-acclimatising.

Behind him, Cormac McAnallen is two matches into his new deployment at full back and will have his hands full with Kerry's newcomer Declan O'Sullivan.

If Tyrone have a specific advantage it is probably in the footballing threat posed by their defence. It's fair to assume that, in the biggest match the county has played in seven years, focus won't be a problem, as it seemed to be against Derry and Down.

Accepting that the four goals in the drawn Ulster final were an aberration, nearly all of the others conceded along the way have hardly had any impact on the matches. It's worth remembering that in the league Tyrone had the best defence, and if spring data isn't generally the most reliable, this statistic demonstrates at least cohesion and marking ability.

In addition, they will exert pressure on Kerry's forwards, creating defensive duties that not all of the Munster champions' attack will be in a position to discharge.

This is particularly hard to call because of the mental pressures on either side. Kerry have won two All-Irelands and know that this hurdle in nothing new.

But Tyrone have been the most consistently impressive side this year and, in the absence of any clarity on the less tangible issues, that's enough to be going on with.