Michael O'Neill acknowledged his Northern Ireland team's introduction to major tournament football was an eye-opening experience as they were beaten in their first fixture at a finals since 1986.
Arkadiusz Milik's 51st-minute goal consigned O'Neill's side to a 1-0 Euro 2016 loss to Poland in Nice, 30 years to the day since Billy Bingham's side were beaten by Brazil at the Mexico World Cup.
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For a team that started two wing-backs who ply their trade in England's third tier, O'Neill conceded facing the likes of Milik, Robert Lewandowski and Grzegorz Krychowiak on such a grand stage may have been a shock to the system.
"I felt they started very brightly, maybe we didn't expect that type of start," O'Neill admitted.
"If you look at our team the two lads that were playing in the wing-back positions, they play their club football at League One level.
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"It was a massive game for us to come in, (with) fantastic support and the prestige of the game. Everything around the tournament has been top class.
"Maybe there was an aspect that it did take us a while to settle into the game.
"We found it difficult to get a foothold into the game and I think that was partly down to that physicality. I don't think we won enough second balls.
"They were very, very powerful in every area of the team and that's something we're going to have to adapt to very quickly, because I don't envisage Ukraine will be any different prospect in that respect.
"Having got the opening game out of the way, we have to do better and see what we can take out of the second game."
While the margin of defeat was slender, the statistics were telling.
Northern Ireland had only two attempts on goal, neither of which were on target, and the Poles enjoyed over 60 per cent of possession in both halves.
"I don't think we ever envisaged coming into this game thinking we'd be disgraced, but there's a bit of disappointment in the dressing room that we didn't do as much with the ball as what we could have done," O'Neill added.
"Individually maybe the players felt they could have done better, collectively we couldn't have asked for any more than that."
Part of the problem appeared to be the change in system.
O'Neill left Kyle Lafferty up top on his own and he was clearly isolated for much of the contest, with the likes of skipper Steven Davis unable to provide ample support.
"We have to give them a system that gives us a chance and we did that. It was 0-0 at half time and 1-0 until right up until the death," O'Neill said.
"The disappointment is that maybe in qualification that's a game we might have taken something from."
While the monkey of a first victory at the Euros is off Poland's backs, head coach Adam Nawalka is not prepared to entertain the idea that they could be a surprise package in France ahead of their next meeting with world champions Germany.
"In terms of our expectations, we are very positive and have a very positive approach to this tournament," he insisted.
"I don't want to over-analysis if we will be the dark horses. We want to achieve good results and be focused on the next match, first and foremost.
"All of our players played very well and I believe everyone will be in great form, we are prepared for some tough moments and I hope it will play out according to our expectations.
"The result doesn't not change our plans about how we want to play against Germany and how we want to prepare. We want to prepare for the win. We have been preparing for Germany for a long time."