Write Monaghan off at your peril. It's their tenth straight season in Division One and despite naming three debutants in the starting line-up they have caused an early season shock in HQ.

A penalty from Jack McCarron and Stephen O'Hanlon's strike meant the Farneymen went in level at the break having conceded an early goal.In the second half, Dublin threatened to pull away moving into a 1-10 to 2-4 lead with 57 minutes gone. But Ciaran McNulty's cool finish soon had Monaghan in front and after a back-and-forth in the closing stages his injury time eventually proved decisive.

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The league is back - and how!

We're going to need a lie down after a head-spinning opening day of Allianz Football League action.

It's been a good day for the Ulster counties, too. While Fermanagh were held to a draw in Division Two by Meath earlier, Armagh got up and running in the second tier by edging past Louth at the Athletic Grounds.

There was also a four-point win for Cavan over Kildare in Division Two with Paddy Lynch hitting 0-7 for Raymond Galligan's side.

And there was drama aplenty in Division One with Mickey Harte's Derry beating Kerry in Tralee before Monaghan's enthralling one-point success over All-Ireland champions Dublin at Croke Park.

Thanks for following along today. We're back to do it all again tomorrow!

Monaghan have beaten the All-Ireland champions in a thriller at Croke Park.

Brian Fenton is dispossessed and Monaghan race down the other end with Ciaran McNulty curling over.

LEVEL!

A beautiful strike off the ground from Dublin netminder David O'Hanlon leaves nothing between the teams heading into four minutes of injury time.

Colm Basquel spurns a golden opportunity for the Dubs palming wide with the goal at his mercy.Killian O'Gara and Ross McGarry brought the home side back on terms but Stephen O'Hanlon's huge point keeps Monaghan in the lead.

They won't lie down. Ciaran McNulty cooly slots home for Monaghan after Darren McDonnell and Andrew Woods had brought them back to within a point.They lead by two with ten minutes to go.

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The All-Ireland champions are beginning to flex their muscles with a trio of points from Costello, Paddy Small and Colm Basquel.

He's huffed and he's puffed but eventually Jack McCarron kicks over after a free at either end to restore parity once more.

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Stephen O'Hanlon almost scores a superb solo goal but is denied by a strong hand from namesake David in the Dublin goal.

Ross McGarry's mark is the only score so far in this second period and sees Dublin hold a slender lead.

Second half is underway.

Despite Cormac Costello's major inside four minutes, the Farneymen have responded brilliantly. Jack McCarron's converted penalty gave Vinny Corey's side a route back into the contest.Costello, Ciaran Kilkenny and Eoin Murchan have all split the sticks for the All-Ireland Champions but Stephen O'Hanlon's goal towards the end of the half leaves the sides on par at the interval.Monaghan making a game of this. Second half to come...

Monaghan are right back in it!

Jack McCarron blasts home from the spot after a foul on Michael Hamill.

A pair of frees from goalscorer Cormac Costello sees Dublin extend their lead while Jack McCarron fails to reduce the arrears, firing wide from a dead ball of his own.

The Farney men are keeping in touch at Croke Park.

Jack McCarron responds with a score after Luke Breathnach landed a mark for the Dubs.

Armagh hang on by the skin of their teeth for a one-point victory as Sam Mulroy leaves a last gasp 45 short of the target.

It was drama to the last and Armagh will have Conor Turbitt and Stefan Campbell to thank as their combined tally of seven points ensure that Armagh open their Division Two campaign with a win.

An early goal from Cormac Costello has given the All-Ireland champions immediate control but Michael Bannigan has since hit back for Monaghan.

In a repeat of last year's All-Ireland semi-final Monaghan take on the Sam Maguire holders Dublin in Croke Park.Vinny Corey has to cope with the loss of Kieran Hughes through retirement. Rory Beggan has his eyes set on further afield while Conor McManus doesn't make the squad.Meanwhile, Dessie Farrell has selected a strong Dublin line-up which includes 2015 footballer of the year Jack McCaffery.Eoin Murchan, Brian Fenton, Ciaran Kilkenny, and Con O'Callaghan are all in from the start for their first appearances of 2024.

Dublin: D O'Hanlon, E Murhcan, S McMahon, L Gannon, G McEneaney, C Murphy, J McCaffery, B Fenton, L Breathnach, R McGarry, L O'Dell, C Kilkenny, P Small, C O'Callaghan, C Costello.

Monaghan: D McDonnell, R Wylie, K Lavelle, R O'Toole, R McAnespie, K Duffy, K Loughran, J Wilson, G Mohan, S O'Hanlon, M Bannigan, M Hamill, D Garland, J McCarron, J Irwin.