Kristoffer Ajer believes that he has improved enormously this season since getting game time under his belt.

The Celtic defender has been a mainstay in the Hoops backline since December and impressed in the opening leg of the club’s Europa League game against Zenit St Petersburg last Thursday night.

It was a far more comfortable performance that the nervy display against Astana at the start of the campaign and Ajer believes the exposure to regular game time has been pivotal to his development.

Read more: Neil Lennon: Celtic can go all the way to the Europa League final this season - if they can beat Zenit

The teenager has gone from being a bit-part player at Celtic to an established defender in the past few months and he is ready to take the next step on his development.

“It wasn’t frustrating for me not to play in the Champions League group stages,” said the Norwegian. “I know when you play for Celtic it’s a fantastic squad and everyone is looking to perform well.

“I’m 19 years old. I need to take my chances when they come along.

“I feel I’ve learned a lot from the gaffer and the rest of the staff both in training and in the games I’ve played.

“I think I’m developing every single day. I didn’t think I’d develop quite as much as I have done this year but it’s a great feeling. I’m getting more and more games. With each one, I feel stronger.

“I just played my normal game against Zenit. The whole squad played with confidence. That makes it easier for a centre half to do their job.”

Celtic have a precious if narrow lead to take to Russia courtesy of Callum McGregor’s goal last Thursday night.

Read more: Former Rangers winger Andrei Kanchelskis tells Zenit to park their squabbles for Celtic clash​

Ajer, though, believes that it is vital for Celtic to approach the game as though it is still goalless.

“It was a great performance and we deserved to win but we know they can hurt us in St Petersburg,” said the teenager. “It will be a tough game.

“The positive is we’ve shown them we can defend even if they put us under pressure. We have no fear about that.

“We’ve shown that in several games. We’re travelling there with the aim of going through.

“I think the tie is still in the balance. In these European games, it’s still very open. They can get an early goal and then we are back at 1-1.

"But we’ll go there focused. The key is thinking it’s still 0-0 knowing we still have to perform to our best levels again. If we do that, we have a great chance.

"If you score a goal away from home having not lost one in the first game, they need three. So we’ll go and try to perform at the same level we did here and hopefully get another good result."