Kristoffer Ajer has hailed the influence of Celtic manager Brendan Rodgers on his career as the 19-year-old prepares for his first senior cap.

The Norwegian defender, signed by Ronny Deila in the 2016 January transfer window, has come to the fore since December at Celtic.

Upon signing for Celtic, Ajer returned to his homeland to finish the season with IK Start before returning to Glasgow just as Deila had left his post.

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He was confined to the underbelly of the club until he headed out on a six-month loan spell to Kilmarnock last term, a move that he has revealed was closely monitored by Rodgers.

The level of detail the Celtic manager put into overseeing Ajer’s loan deal will please the likes of Anthony Ralston who has headed out to Dundee United on an emergency loan and Conor Hazrd who headed out in January.

And Ajer has insisted that it was not a case of out of sight, out of mind.

“He [Rodgers] is incredibly vigilant when it comes to his players,” said Ajer.

“When I was on loan at Kilmarnock I often got feedback and went to our training centre to go through what I did in clips of matches.

“The information I received was crucial for me and gave me the indication that when I returned to Celtic I could get some playing time.

“He used to text me after matches about what I did well and what needed to be improved. The feedback Brendan Rodgers gave me was invaluable.

“He is on the pitch at every single training session and it is very important for him to join in and see and help all the players.

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“He demands 100 percent of his players every single day and when you are in such an environment where everyone will develop all the time, you improve yourself too.

Rodgers recently lauded Ajer for his willingness to learn, describing the player as imminently “coachable”. One recent moment against Zenit as Ajer celebrated Celtic winning a throw-in caused a few ripples of amusement among the Hoops fans as the clip did the rounds on social media with Rodgers among those who had a smile at the youngster’s enthusiastic reaction.

Certainly, though, it has been Ajer’s own willingness to take on the challenge of getting into the first-team – and staying there. Given his chance in the immediate aftermath of the defeat to Hearts at Tynecastle in December and when Celtic’s treatment room was full the player has nevertheless managed to maintain his place.

Ajer was heavily involved in the win over Rangers at Ibrox earlier this month when ten-men Celtic twice came from a goal down to take all three points and there are suggestions that he and Jack Hendry could ultimately go on to form a lasting partnership in the middle for Celtic.

Rodgers has converted the player from the midfielder he was when he first arrived at the club to a centre-half but for Ajer the mental approach of being in the right frame of mind to win every game has been as important as anything else.

“Celtic have a crazy winners mentality and the club is about showing how you can contribute to that,” he told journalists in his homeland.

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“You have to show that you want to work hard and get better, and I did that from the very first moment. I wanted to show I was good enough to play for Celtic and they respected that.”

And while Rodgers has been a major influence on the player and his development, there has also been a lot of work done on the training ground with former defenders John Kennedy and Kolo Toure.

The duo often oversee extra sessions with those at the back and Ajer believes that he owes them both a debt for the manner in which he has developed.

The teenager has represented Norway at every age level from under-15 but expressed some surprise that his call-up to the senior side came a little earlier than he would have anticipated. Norway played Australia last night and will also have another friendly against Austria on Monday and Ajer has been delighted to be involved with the squads when he is still eligible for younger levels.

“I am very lucky to play for such a great club as Celtic with a fantastic manager and a great support team,” he said. “Both Kolo Toure and John Kennedy have helped me a lot too.

“Certainly, I have developed faster that I would have thought.”