IN many ways, it is hard to believe that Kristoffer Ajer is only 20. His physical stature for one belies his tender years, and the authority and assuredness with which he speaks even more so.

That’s why it is difficult to doubt him when he says that he is ready to handle the pressure of marshalling the Celtic defence through their Champions League qualifiers in the absence of Dedryck Boyata.

With the Belgian excelling at the World Cup with his country, it will likely fall to Ajer and Jozo Simunovic to be the defensive bedrock upon which Celtic’s quest for qualification to the competition’s group stages will be built, and the young Norwegian internationalist is relishing the responsibility.

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“First and foremost I’m just delighted for Dedryck playing so many games in the World Cup and playing well,” Ajer said. “He’s worked very hard for this, so it’s fantastic to see.

“There’s always responsibility when you play with Celtic. When you play for such a massive club with expectations of winning every game there’s always pressure when you play.

“That’s why you love being a footballer, to play in those special games. Hopefully they keep coming.

“Every Champions League qualifier is really tough, and we need to be 100 per cent up for them to go through and that is our plan for these games.

“You can never take a game easy in the Champions League qualifiers, because you know you are meeting winners from different leagues and they will be right up for it.

“Of course, it will be warm [in Armenia] and that’s a challenge for us. But we’re really looking forward to it. We’ll come fit and ready to play.”

Despite his youth, Ajer already has experience of where things can go awry at this critical juncture of Celtic’s season, having played in the salvage operation second-leg tie against Gibraltar minnows Lincoln Red Imps back in 2016.

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“That proves that every team you meet in Champions League qualification can hurt you if you are not 100 per cent ready on the day,” he said.

“We will be 100 per cent ready and focused. We will know everything about our opponents.

‘You just have to accept that there’s an extra round this year and be ready for all the challenges that are coming. We are meeting a good team from Armenia in the first round and that’s our only focus right now.”

Ajer’s conviction only subsides slightly when discussing his own place in the pecking order at Celtic, retaining a sense of modesty and a hunger to continue to prove himself in spite of the strides he has made over the past year in particular.

That’s why he has come into the pre-season training camp in Austria with a mindset to show his manager what he can do all over again.

“I look at it as a completely the same as last year,” he said. “I still have a lot to prove, I only played half a season last year and I need to develop a lot in my game to be a Celtic player.

“So, I’m just looking forward to the challenge and hopefully I’ll be involved this year as well.

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“I feel I am developing well, I’m learning a lot from the gaffer, the staff and all the players around me, it’s a fantastic environment to be a part of.”

Meanwhile, Celtic boss Rodgers is set to give Moussa Dembele his first run-out of pre-season in one of the two matches that his squad will take on tomorrow. The Scottish champions will face Blau-Weiss Linz in a closed-doors friendly in the morning before a different line-up takes on Sparta Prague in the afternoon in the Austrian town of Rohrbach.

“Moussa came back a bit later than everyone else, but he looks really, really fit,” Rodgers said. “He had a slight issue with his knee the other day and we took him out of one of the sessions.

“We didn’t want to risk it and push him for the Bohemians game, but he’ll be involved on Tuesday. Moussa has come back really fit, he’s lost weight, he looks really good in his running. He’ll be fine.

“All the players will be undercooked in terms of games, that’s the reality.

“But Moussa has returned in good condition and we still have time to go [before the qualifiers].”

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Rodgers is also ready to give Ryan Christie and Scott Allan, who have both returned to the club following loan spells last season, a chance to play their way into contention after impressing him so far during the trip to Austria.

“The two boys have initially come back and my duty to them is to make sure they are at their highest level fitness wise,” he said. “Then we’ll see over the course of the pre-season.

“Both players have looked very good. When I look at Ryan’s situation, it was to get him out and get him stronger. The Aberdeen loan was perfect for him.

“It’s partly where these boys see themselves as well. I might want to keep them, but if I can’t give them as many games as they want, then it’s difficult. But both boys have come back looking strong and looking fit and have done very well.

“I never rule out any player. I use my eyes, I look at how they train, I look at their commitment.

“I don’t rule out any player, especially when you’ve got good players.”