Martin O’Neill keeps saying of late that anyone could probably list off 80 or even 90 per cent of the squad he will bring to France in a couple of weeks. But that leaves a dozen or so players pitching for a handful of places on the plane – and half as many again anxious not to count any chickens about the choices the manager will make over the coming days.

A slight knock to Shane Long, which caused the striker to end his involvement in the second day of training, was the most significant development at the Aviva Stadium, where a few thousand supporters, mainly kids, turned out to watch the squad go through its paces.

Long was said to be fine, and the atmosphere in the sunshine was relaxed, but beneath the surface there is competition to catch the manager’s eye as he weighs up team selections for the games against the Netherlands and Belarus that may, in turn, have a decisive impact on who makes that final squad of 23.

Shane Duffy appeared to take a very big step towards the departures gate on Monday when Marc Wilson was ruled out and Paul McShane and Alex Pearce got early indications that they may not be required. Still, it is no surprise that the Blackburn centre-back is cagey about the prospect of playing a part at a European Championship. He knows better than most how quickly things can change in a training camp.

Then at Everton, where he appeared to be regarded as a real prospect, Duffy made his first appearance in the Ireland set-up six years ago, when a freak accident in a game against a team of local amateurs left him requiring emergency surgery.

There have been occasional call-ups since, but only two caps, and it was really only with the second, against Switzerland in March, that the 24-year-old staked a proper claim to a place among O’Neill’s regulars.

He has, in the meantime, endured some tough times at club level. After various loan spells, the Derry man eventually had to give up on his dream of a breakthrough at Goodison, then wait to establish himself at Blackburn.

Recognition

In the circumstances, he admits, he probably hadn’t done enough to earn greater international recognition. After a fine second season at Ewood Park, he is hoping that has changed.

“I probably wasn’t ready, to be honest,” he says of the years spent on the margins of the Irish set-up. “I probably had to go out, drop leagues and learn a few things. I’ve still got a lot to do, I think, but I’m happy the way it’s going at the minute. I got a reward in getting called up, so I must have been improving.

“The manager [Paul Lambert] was key this season. He took me to a new level. The season before, I was up one week, then down. But he helped me get more consistent, and I’m gutted he’s gone. He was brilliant for me, he liked the way I played, and he gave me confidence. And confidence is such a big thing for me. I think I’m full of it now at the minute.

“I made a few mistakes and had to bounce back and learn from them, just practising what I’m good at and trying to get better and better every day.

“ I’ve got a lot better on the ball. If you want to step up, you have to be comfortable on it the way the game is going. So I have worked a lot on that. My physique too; I’ve got a lot fitter and got stronger. Obviously I’ve tried to get better and what I was already good at, in the air, stuff like that.”

Lambert certainly gave him game time, with Duffy making more than 40 appearances for the club.

Best of the season

There were a handful of goals, too, including the one voted the club’s best of the season, against Brentford. That ability to pose an attacking threat, O’Neill has acknowledged, is one of the reasons he has taken to the player at such a key time.

The manager may still be asking a lot of him, given how little international football he has played, but Duffy seemed entirely at home in yesterday’s open training session at the Aviva Stadium and unfazed by the idea of trading the hustle and bustle of the championship for the somewhat higher-class challenges that await in France.

"They're just names really," he says when the likes of Zlatan Ibrahimovic and Graziano Pellè are mentioned. "I try and thrive off being big and strong and winning headers, being strong in the tackle. They've a big presence, obviously they are superstars in the game, but they are just names really.

Anyway, he says, “I can’t get ahead of myself, I have to get there first. That’s my main aim. It’s a massive week and I want to try my best.”