It was the hour after Gareth Bale’s return from injury for Real Madrid against Espanyol on 18 February and, with the 27-year-old already smiling given that he had scored, he suddenly started laughing. The Welsh star was talking about when he had posted a photo of himself back in training on Twitter, only to immediately be deluged by hundreds of Irish people expressing their exasperation in expletives.

That’s the pedigree of Bale, that’s how good he is, and that is the major difference between these teams. It is why Wales were capable of getting to the Euro 2016 semi-final, and why Ireland were relatively content with the last 16. Chris Coleman has a bona fide world star, while Martin O’Neill doesn’t really have anyone close to that level.

It is also one big reason why Coleman does not have too many concerns about the fact Ireland are currently four points ahead of Wales at the top of the group with just six games left ahead of their meeting in Dublin on Friday, even if he typically played up the team over any one player.

That is something Irish assistant manager Roy Keane will obviously recognise, and it was so pointed that he was so gushing about Bale in his own Wednesday press conference, in a way you never really see from the usually cynical Irish legend.

“He’s a top, top player, a brilliant player,” the 45-year-old said. “He’s been doing it right there at the highest level in the last few years. I’ve always liked him… He’s a talented boy who has fulfilled his potential and probably more. Our lads should look forward to the challenge - you should want to play against and play with the best.”

Keane would have. When it was put to him that he might have kicked Bale to stop him had they played against each other, he reduced the questioner to one of those typically hard Keane stares, before responding: “'He might have been more worried about me. I could play a little bit too you know.”

He will also know Bale’s situation. The Real Madrid star is to Wales exactly what Keane used to be for Ireland, what Cristiano Ronaldo is for Portugal, what Zlatan Ibrahimovic used to be for Sweden and the latest in a distinguished but distinctive line that offer a unique dynamic in international football: that one single world-class player in a mid-sized international side who greatly lifts the level of the team in general, but can raise them to scarcely imagined levels when on particularly impressive individual form.

They also have that oh-so-noticeable aura, receiving an attention their countries aren’t usually accustomed to, and playing on the minds of opposition. They signify that this is not just a good over-performing team to be respected, but that they have a player to be feared. They carry that rare responsibility, because they have that rare talent.

Gareth Bale: We have more passion than England

It summed it up that, in the build-up to what is genuinely a crunch qualifier and probably the most important in all of Europe this week, one of the most notable events was Keane - the current Irish assistant - being repeatedly asked about Bale. That is how they got onto the subject of kicking.

“'Don't give him space in behind, because the boy can run," Keane said. "Tackle him. Hit him… fairly. Tackling is part of the bloody game.”

Coleman correctly stated that it is nothing that Bale won’t already be accustomed to, and Keane argued that a player of that ability has the capability of making any gameplan moot.

“'What you find is that coaches have tried to come up with a plan before but top players figure it out and affect the game anyway.”

For all the similarities in situation between Keane and Bale, though, there is a significant difference in dynamic. Bale just looks to have a much happier and enthusiastic relationship with his international set-up than Keane the player did, and also than one of the Manchester United legend’s teammates - and Bale's worthiest predecessors - in Ryan Giggs did.

That was the case before Euro 2016, of course, and will only be amplified when you so exceed expectation in the way Bale did. His supreme international legacy is secure in that regard, and on a different plane to any Welsh player since 1958 World Cup quarter-finalist John Charles. He made history for his country by firing them to their first tournament in 58 years, and then made international history by ensuring they were one of those special few sides to have reached a tournament semi-finals.

Bale has passed every international challenge so far, and done it with such relish.

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While there can obviously be absolutely no questioning him, then, this match in Dublin still represents a different challenge and one where they need him to be on that kind of higher plane again.

Wales have the opportunity to make it two tournaments in a row but, to take it, have to start by getting a result away to a very resolute Ireland. And that in a context where, as Coleman put it, Wales are now a “scalp”. It would similarly be a huge personal disappointment if Bale missed the opportunity to play in a World Cup in his physical prime, like so many similar massive stars from moderately-sized countries like George Best.

To better that, Bale has to dig in, to show [how] he is the difference between two otherwise well-balanced teams.