Looking around the dressing room at half-time in their All-Ireland quarter-final against Mayo, Karl Lacey saw in the eyes of his colleagues something he hadn't seen in 17 previous championship matches across three years under Jim McGuinness.
For the first time, he saw a group of players without the conviction to fight. There and then, he sensed it was over.
Lacey had come on as a replacement 24 minutes in, when the All-Ireland champions trailed by 2-4 to 0-4. By the break that six-point deficit had doubled and at 2-10 to 0-4 the game was up.
"It was probably the longest..." he trails off softly. "At half-time, I remember Jim saying, 'we're still in this, we still can win this'. He still had the belief that we could go out and put in a big performance, but you could see it in boys' eyes in the dressing-room, 'how the hell are we going to get this back?'.
"That was a wee bit disappointing, the fight had nearly gone out of us at that stage, whereas Jim was trying to push us on a wee bit. In my three years under Jim, I never saw that happen before."
For Lacey, Donegal were always playing 'catch up' in 2013. They never quite got there. Ten minutes into the Ulster final against Monaghan, his legs felt like jelly. Around St Tiernach's Park, as Monaghan hit them for four unanswered points to lay down a firm marker, Donegal's collective foot-print was all too sluggish.
"You're looking around and you know you just don't have it in the legs. The hunger was there and we thought we were in a good place," he says.
"Every man was trying their best but we just didn't have it in the legs, didn't have the endurance, didn't have the speed or sharpness. You're looking over at the sideline and asking Jim, 'what the hell's going on here?' Jim didn't have the answers.
"It was a funny year coming back from everything that happened in 2012 and going away on a team holiday, coming back on January 8. You're straight in to National League nearly and you've no pre-season done, no base built up.
"We were just playing catch-up from there and never got up to the levels that any of the other teams were at. We were found out against Monaghan in the Ulster final and started to go downhill really from there."
It rankled with him that Donegal's hunger for a third successive Ulster title could be questioned.
"It was a wee bit frustrating to hear that. The hunger was definitely there. We wanted it, we were going for three in a row, something that was never done in Donegal and would have been legendary status if we'd got it."
For Lacey, the frustration of those defeats was compounded by his own predicament. He missed the entire league campaign after hip surgery in December, the legacy of a punishing club campaign with Four Masters that forced him into six games in 22 days.
He made it back to feature for the last 20 minutes of the Tyrone game in Ballybofey, but a knee injury while on duty for the club again sidelined him for the Down clash. With Monaghan ranging into view, Lacey just didn't have sufficient work done for the game he likes to play.
Did the physical and mental toll of being All-Ireland champions for the first time in 20 years have an impact in those two weeks at the end of July and into early August?
"There's a lot of things that go with winning an All-Ireland and these things have to be done as well. Personally, it was new to all of us.
"We thought... Jim thought... that if we came back in January that we would have enough time, but when you look back on it now, we didn't. If you were to win it again, I'm sure you wouldn't take as much time off," Lacey concedes.
The 2012 Footballer of the Year's personal circumstances have changed too. On Monday, he begins a masters in sports performance at the University of Limerick, leaving behind a four-year career with Ulster Bank and following the same pathway as his former banking colleague, Kilkenny hurler Michael Fennelly.
Being based in Limerick will present its challenges, but not enough to throw him off the scent of another Ulster title or All-Ireland.
"It's further away I'm getting," he laughs. "I was in Dublin last year (in Ulster Bank's headquarters), now I'm in Limerick. With the demands in the game and the commitments you have to make it's not easy.
"Jim has been very good. We will work around it, we have looked at the timetable and set dates in place, days I have to come and days I don't. I'll not let it affect my preparations. There is a good set-up down in Limerick and I'll be training hard down there. We will work around it."
Lacey suspects McGuinness himself will want to "prove a point", but it will be without his old sidekick Rory Gallagher after his departure in September.
"It's was unexpected, quite a shock. But you have to respect the manager's decision and if he thought that was the best way – I think the two of them agreed it – to go forward for the team then we have got to believe in that," he says.