Monaghan manager Séamus McEnaney paid tribute to the county's U20 captain, Brendán Óg Duffy, after their Ulster Senior Football Championship semi-final win over Armagh on Saturday.
Duffy tragically died in a car accident on Friday night after guided his side to an Ulster final with victory over Donegal.
4-17 to 2-21 was the final score on Saturday in what was an emotional occasion in Newry.
Speaking to OTB Sports at full-time McEnaney said he found the news hard to believe.
"It was devastating, for me personally and for the group. This man was my minor captain three years ago, he was a fantastic young fella.
"He had a huge future in front of him in this Monaghan dressing room next year and thereafter.
"It was devastating when I got the news last night at half-one, I hadn't slept at that point with the heat but i didn't get any sleep thereafter."
Duffy's club Monaghan Harps and Monaghan GAA released statements expressing their sorrow and sympathies to the 19-year-old's family.
GAA President Larry McCarthy also offered his condolences and praised Duffy's character and talent.
McEnaney said his players dealt with the gravity of the occasion well, detaching from the emotion of the day to put in such a performance.
"We talked about it, I done a lot of homework before I went into the team meeting this morning to make sure that I set the emotions aside for this team and this group of players.
"I think we done that and I'm absolutely delighted for the group."
Monaghan will now face either Donegal or Tyrone in the provincial decider in two weeks time as they aim to win the Anglo-Celt Cup for the first time since 2015.
After leading by seven points at half-time many thought this game was only going one way.
Armagh produced a serious comeback however and Monaghan had to cling on for the two-point win in the end.
McEnaney though felt this highlighted their resilience and was full of praise for them.
"I was very impressed with my own side right throughout the game, until the very last kick of the game.
"We played some fantastic football.
"We grinded out scores when the game went against us, especially at the end with five minutes to go we looked like we were dead and buried but these boys are made of character.
"We don't have to build leaders, Thank God, I've loads of them in the dressing room."