An incredible day at Croke Park as Fermanagh conjured one of the shocks of modern times. The margin of victory might have been just one point but the reality was that they ran Armagh off the field and should have won by five or six.

In missing several gilt-edged chances in the final 20 minutes, Fermanagh appeared to be fighting one final hurdle, that of mentally accepting their right to victory. When they finally got rid of that fear they were able to complete the task.

Maybe we should have seen it coming with the wins over Meath, Cork and Donegal; if Armagh had arrived at Croke Park with the same list of scalps we wouldn't have dismissed them as readily. Fermanagh will now be a match for anyone.

The winners hardly received the ideal start to calm nerves. Armagh raced into a four-point lead and the expectation was that the rest of the match would follow the prepared script. They were strong and purposeful on the ball, Diarmuid Marsden and Steven McDonnell winning possession and taking scores.

Colm Bradley's first score, in the 12th minute, had a settling effect and Stephen Maguire began to get on the ball and pull the strings. Fermanagh were moving ball quickly and using the diagonal ball to trouble Armagh. Maguire kicked one inspirational score from under the shadow of the Hogan Stand, falling as he kicked it.

Armagh didn't panic and were unlucky to see Marsden's flick come back off the crossbar. Still we waited for them to put Fermanagh in their place. The key element in sustaining the Fermanagh challenge was pace: they had it and Armagh lacked it.

Enda McNulty's tackle was both high and late and that incident along with the one involving McDonnell highlights the fickleness of fate. Both were guilty of striking. One received a straight red card, the other saw yellow.

The question coming up to half-time was how Fermanagh would use the extra man. They deployed corner back Niall Bogue to police the space in front of Marsden and McDonnell. It helped cut off the supply.

Armagh showed their experience in that they twice came back to lead in the second half despite being down to 14 men, Kieran McGeeney kicking a point and, later in the half, substitute Oisín McConville nudging them in front at 0-11 to 0-10.

Fermanagh, though, refused to be daunted. In Tom Brewster they had a player who was to provide that pivotal scoring fillip on the run-in to the final whistle, his fitness and work-rate causing Armagh serious problems. Despite some glaring missed chances it would have been an injustice had Fermanagh lost or Armagh drawn the match.

Armagh had played brilliantly against Monaghan and Donegal but were nearly caught by Cavan and finally undone by Fermanagh, showing how hard it is to maintain a very high level of performance from one match to the next.

Fermanagh are in dreamland and won't have too many detractors ahead of their All-Ireland semi-final against Mayo. Individuals like Ryan McCluskey, Barry Owens and Martin McGrath were outstanding on the day.

As for Mayo, their win will have been a massive confidence boost.

The loss of Brian McGuigan was a huge blow to Tyrone. He was their distributor-in-chief and the fact he was replaced by a wing back highlights Tyrone's thinking before the match.

The All-Ireland champions had lost the spine of their team before the interval, with Conor Gormley and, surprisingly, Shane Sweeney making way.

Peter Canavan's introduction was a little earlier than many had expected and one wonders about his absence the last day.

Only Ryan McMenamin and Philip Jordan were holding their own defensively while, for Mayo, players like Alan Dillon and David Brady were accepting responsibility with relish.

Brady kicked three points on the day and in the midfield battle we had flagged as being critical he and his partner Ronan McGarrity more than coped with Seán Cavanagh and Kevin Hughes. Peadar Gardiner did a superb job on Brian Dooher. Denied that platform and possession around the middle of the pitch, Tyrone couldn't function as they normally would.

The Ulster side are known for coming out of the traps quickly in matches, playing with huge intensity and getting a lead and then using their blanket defence.

They couldn't get that lead against Mayo and instead found the tables turned quite comprehensively as the Connacht champions gave them a taste of their own medicine.

Stephen O'Neill's goal, ironically, signalled the end of the road rather than the expected comeback. On a day when Tyrone and Armagh were expected to perpetuate Ulster football's ascendancy it is Fermanagh and next weekend Derry that must now don the mantle.