While it may be a strange statement to say after a 5-1 defeat, Northern Ireland showed in Friday’s draw against Switzerland that they can match sides who are regulars at major tournaments.
O’Neill’s team have also impressed against the likes of Scotland and Romania in the past 12 months, but the game in Sweden was a harsh lesson.
Charles, who captained the side at 21, is confident it will not leave any lasting impact on a young panel who had been on an upward trajectory.
“I don’t think it was a 5-1 game, which is always hard to look at when it is that score,” he said.
“They finished their chances, unlike us. I feel that we had similar chances.”
Northern Ireland were without three first-choice defenders in Conor Bradley, Trai Hume and Dan Ballard, while Eoin Toal also likely would have featured if fit.
“We should have been a bit more compact, but we didn’t and it ended up being five,” added Charles.
“That’s what that’s what happens when you do make mistakes against players of that quality.”
