In the opening round of the Dalata Hotel Group Ulster Under-20 championship, a late Donegal rally denied Fermanagh a huge scalp in Buncrana, while Derry proved too strong for Monaghan in Castleblayney.
Fermanagh looked on course for a memorable win over the Tir Chonaill men, but Donegal - without captain Finnbarr Roarty - snatched victory on a 2-15 to 3-11 scoreline after taking the lead for the first time in second-half injury time.
It was a flying start from Ronan Gallagher's visitors, who, despite being seen as huge underdogs, had 1-05 on the scoreboard before Shane Callaghan scored Donegal's opening score of the game in the 11th minute. Mattie McDermott grabbed that Fermanagh major and quickly followed it up with a two-pointer.
However, two goals in a three-minute period – a Kevin Muldoon penalty followed by a Donnacha O Baoill effort - levelled matters as they approached the interval, but the Erne men responded well, raising a second green flag of their own through Daire Chapman to take a 2-08 to 2-06 lead into the dressing room.
In an even second period, Fermanagh kept their noses in front - aided by a third goal from Rory Smyth with just over 10 minutes remaining - until time added on as Donegal dug deep to pick off the final four points of the game.
Kalvin McLaughlin was the match-winner with his injury-time effort ultimately the difference between the sides.
Elsewhere in Group A, Monaghan made the better start at Castleblayney against Derry, with Max McGinnity splitting the posts as the Farney men took the opening three scores of the game.
Ger Dillon, from play and placed balls, kept Derry very much in touch, with the Oak Leaf enjoying a 0-06 to 0-05 lead at the break.
A Monaghan goal from McGinnity five minutes from time levelled matters, but with the game in the melting pot, it was Derry that kicked for home.
The Farney men failed to score again, with Cahir Spiers claiming the final point of the game in a 0-14 to 1-08 victory for Derry.
In Connacht, a couple of late Darragh Beirne scores proved the difference as Mayo left Tubbercurry with a hard-fought 0-17 to 0-15 win over Sligo.
Beirne, Oisin Deane and Kobe McDonald were all on target early on as Mayo took a 0-10 to 0-07 lead in at the break, Eli Rooney providing a real threat for the Yeats County.
The Mayo lead was out to five points 10 minutes into the second half, but Sligo fought back gallantly and they scored six of the next seven points to draw level – Rooney, including one two-point free, responsible for 0-05 of that tally.
That left it 0-15 to 0-15 with just six minutes later but Beirne, with one from play and one from a free, ensured that Mayo took the points on opening night.
Galway also made a winning start as they defeated Roscommon 3-10 to 1-11 in Tuam.
Niall Heneghan's two-pointer gave the Rossies a fine start, but early goals from Shay McGlinchey, with a neat finish, and Cian Mitchell put Galway in control.
John Curran did respond with a fine Roscommon goal from distance as Galway led 2-05 to 1-04 at the break.
The Tribe stretched that advantage out to seven points early in second half – and that was the margin 10 minutes from time too as Matthew Collins fired home their third goal as he did well to keep his footing.
Roscommon finished the better but were unable to get close enough to trouble the result.
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