Astana scare has steeled Ajer for any challenge on Euro stage

● Celtic teenager has learned from last summer’s Kazakhstan wobble and is confident he could cope against Zenit

There is a school of thought – most notably voiced by Kris Commons the other day – that says Celtic’s fraught evening in Astana for their Champions League play-off six months agoprovidesevidencekristoffer Ajer could not be trusted in next month’s Europa League tie against Zenit St Petersburg. The 19-year-old Norwegian would contend that the reverse is actually true.

In Kazakhstan last August, Celtic – defending a seemingly unassailable 5-0 first leg advantage – collapsed quicker than a pound-shop deckchair to lose three early second-half goals and so find themselves 4-1 behind. The unthinkable then became possible before Brendan Rodgers’ men hit back with two late goals to guarantee their place in the Champions League. However, the night seemed to set back Ajer’s development when it came to taking the European stage for the club. He hasn’t appeared on it since.

The teenager in no way reflects on the Astana encounter as a downer, though, but instead a game to set him up for Zenit should he be given the call – which is entirely possible with the centre-back contributing to four straight clean sheets as he held his place for Celtic’s final games before the winter shutdown.

“It was a really good game for me to look and learn from,” he said. “It was another experience for me. After the game we sat down with some of the staff and looked through my clips and learned a lot from it. We do that after every game and it’s about improving and learning from every aspect.”

Ajer is only one year into his life as a centre-back after being signed from homecountry club Start in the summer of 2016 as a midfielder. He made sufficient progress in his new position across 2017 – spending the first six months of it on loan with Kilmarnock – for Rodgers, pictured, to state the other day that central defence was not a priority area to strengthen in this transfer window. Rodgers offered up this view despite the calf injury sustained by new signing Marvin Compper – who is ineligible for Europe – that will sideline him for a month and the continued form struggles of Jozo Simunovic.

“I’ve developed a lot in the last six months under the gaffer,” said Ajer. “He has helped me a lot and put faith in me. It’s been really good. I feel more secure as a centre-half now. When I came here I was a midfielder but I feel more secure as a centre-half now. I needed time to get into the new role and understand how the gaffer wants central defenders to play. The loan out to Kilmarnock also helped because I played there every single week as a centre-half.”

Yet Ajer knows he can take nothing for granted. Even allowing for the fact that the recent backline partnership he has established with Dedryck Boyata is likely to continue tomorrow when Celtic resume their season by hosting Championship bottom club Brechin City in the Scottish Cup fourth round.

He has strengthened his own claim for a continued senior run by embarking on a gym programme that has resulted in the previously lanky 6ft 5in defender becoming an evidently more muscular and imposing figure. His willingness to put his body on the line is clear from the no-holdingback approach he takes into games, but he says that has to be a given.

“It’s something different to play for Celtic. When you