Celtic kid Kristoffer Ajer will look to get one over his international colleague Tore Reginiussen when Brendan Rodgers’ side host Rosenborg next week.

Ajer will come up against his fellow countrymen in Celtic’s second round UEFA Champions League qualifier and is looking to have the last laugh.

Reginiussen lined up alongside one another this summer for Norway but there will be no friendship issues allowed to get in the way next week as they battle for the upperhand in the opening leg of the qualifier.

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“I know the centre-halves at Rosenborg really well,” said Ajer. “I play with Tore for the national team. They’ve got a really good, strong back four. It will be interesting to see the game next week.

“I think they have many good players. But Rosenborg are a well built team with a manager who has been there many years. There is a really clear structure. I think they have a really good team that will make it difficult for us.

“Nicklas Bendtner is a very good player, a really good striker. We haven’t looked so much yet for our next opponents. But we’ll have a look at it this week, of course.”

Having coasted through their opening qualifier against Alashkert, Ajer expects the bar to be raised considerably when they meet Rosenborg next week.

“I think when you play Champions League qualifiers you meet quality opponents,” said the defender. “I know Rosenborg really well and last year they beat Ajax in the last round to go through, so they’re really a top side.

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“They can really hurt you if you’re not 100-per-cent up for the game.

“But we know that. When they come here next week then hopefully we’ll put on a really top performance. We also know that they’re a great team.

“Rosenborg is a typical Scandinavian team, well organised and have a good squad. So that’s probably their biggest strength.

“Rosenborg is a really tough opponent with a lot of quality players. It will be a really tough game both home and away.

“Obviously I like going home and it will be nice returning to Norway. But I play for Celtic and I’m just looking forward to the two games. Rosenborg will make it difficult for us and it will be an exciting game.

“I think it’s another European game for Celtic and another tough game, also for me to hopefully to play. If the gaffer selects me it would be another big game for me to get experience and hopefully play well.

“I think it will be. Rosenborg will come here and make it difficult for us and also over there. They will be tight games, they’re a good side.”

Celtic haven’t had too much surgery since they played the Norwegians at the same stage a year ago. That should mean that both sides know a fair bit about one another but Ajer is confident that Celtic can be more convincing this time around.

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“Obviously, it helps us knowing a little bit more about the team,” he said. “Since then they’ve made some team changes, a few more signings. Obviously, we’ve also had some signings too, so it’s slightly different.

“But, we know them better that we did last year. To be honest, we know that you can play good games, but that you always need to think about the next game.

“Things can change from one game to another — so you need to be 100-per-cent focused.

“Rosenborg is a great team and we need to be ready for that.”

And Ajer is reluctant to take anything for granted. The teenager broke into Rodgers’ first-team at the turn of the year and has been a mainstay ever since but he is well aware that he needs to kick on again this season.

“When you play for Celtic you always need to put on a top performance to keep your spot in the team,” said the defender. “I just need to be 100-per-cent focused over the next few days. Hopefully everyone else can stay fit and we’ll be raring to go.

“The manager makes sure you know that every time you play for Celtic it’s a big game. When you put on that shirt you always need to put on a top performance. That’s what we hope to do.”