IT’S probably just as well that Callum McGregor isn’t one for swapping his jersey with the opposition, no matter the storied names he may be coming up against.

Given that he will play his 92nd match in European competition for Celtic against Atletico Madrid, he might need an extension to house them.

His mum, however, does keep a hold of the shirts he scores in, which - with the greatest of respect to the Celtic captain - is an altogether more modestly sized collection. If he manages to bag one in the Civitas Metropolitano though, she may have a fight on her hands to get it off him.

“It’s not for any particular reason, I just never started doing it so I’m probably too old to start now,” McGregor said.

“A lot of the boys do it but it’s never been me. Maybe if I started way back then, I’d have some decent ones.

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“I’ll just need to keep putting all of mine up on the wall. I keep the ones that I score in. The others go to charities and other things.

“If I score in one my mum takes it. She’s got a big double sized wardrobe with them all in it.

“If I score against Atletico she’ll need to fight me to get that one off me…!”

Before that scrap can happen though, McGregor and his Celtic teammates have an almighty fight on their hands against Diego Simeone’s battle-hardened, star-studded team on their own impressive patch here in Madrid.

It is, in just about every sense, as far removed from their game against Ross County in Dingwall on Saturday as it could possibly be.

Off the pitch, the contrast in surroundings to the Global Energy Stadium could hardly be starker. But on the field too, the differing challenge posed by their opponents will be a marked one.

Celtic registered 39 shots against 10-man County at the weekend, a feat they are unlikely to match here. And McGregor admits their approach to challenges on a domestic front and then at European level have to be different, as much as they will try to impose their style on Atletico.

“We’ll not get 39 shots on Tuesday night, definitely not,” he said. “Unless we shoot every time we get the ball!

“It shows you though that the higher up the level you go then of course the chances become limited, so you have got to convert the chances you do get.

“When you have good spells in the game then you have to take your chances, because ultimately they will have a good spell of possession and we will have to suffer a little but without the ball as well.

“So, it’s just about trying to get the balance of all those things right.

“Domestically we have the ball a lot of the time and it’s about us creating the tempo. We’re trying to move people about, open up space and penetrate, then the longer we do that then we can score and the game opens up from there.

“It’s almost like two different gameplans that you need. A lot of the time in Europe to be fair we go with the intention of trying to be on the front foot and trying to dominate the game but you can’t be a million miles an hour all the time, especially when you play at this level.

“You have to pick and choose your time, and the gaffer is saying we need to have that wee bit of adaptability where we go to the 3-5-2 with 25 minutes to go, it just stems the flow and you can reassert yourself into the game and play your way back in.

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“So, we do need a little bit of variety in that sense, and he is certainly a manager who likes that, and can detail his team to play that way as well.”

That adaptability though will not mean they will sacrifice their principals, even if McGregor – along with everyone at Celtic – is fed up of receiving praise for their performances without the results to go along with it.

“I don’t think that is us as a club, I don’t think that is the direction we want to go,” he said.

“We understand how big the challenge is in terms of the budget that we’ve got against the budget that the big teams have got, but if we have the right quality of player, the right mix and the right system, then who’s to say that we can’t play this way?

“Because if we want to be a top team, then that’s the way all the top teams are playing. They are playing with the ball, they are trying to create chances.

“We understand there is a disparity in quality and budget and all these things, but we try to make up for that by having a structure, intensity, being able to run and create chances.

“That is my belief that it is the way the club wants to go, it suits the group that we’ve got and the recruitment model that we follow ever year.

“I don’t see us being able to change direction and say we are going to stick 10 men behind the ball and try to scrap one out.”