Legendary full-back Danny McGrain made his senior debut for Celtic soon after turning 21 in August 1970, and went on to make a staggering 679 appearances for the club over the next 17 years. Surely, given the nature of modern football, nobody from the current crop of Celtic players will go on to reach such dizzying milestones at the club?

Well, if Kieran Tierney has his way, he may well be a Celt for life, and he already has a head start on McGrain.

Tierney will clock up his 100th appearance for the Hoops today at the tender age of 20. When McGrain was Tierney’s age, he was part of the ‘Quality Street Gang’ alongside the likes of Kenny Dalglish, George Connelly, Davie Hay and Lou Macari, but still awaiting his big chance in the first team and yet to clock up a single appearance.

Suitors are undoubtedly circling for Tierney. And with the money that clubs in England can offer, the future direction of his career may yet veer in a direction away from Glasgow’s East End. As he has repeatedly countered though, he is living out the only dream he has ever had, so why wouldn’t he be able to overcome McGrain’s lofty record?

“How many games did he play?” asked Tierney, before adding once informed of McGrain’s tally; “That’s mad, isn’t it?

“I’m just taking it as it comes, I don’t take anything for granted and work as hard as I can every day.

“The more games I play the better it is for me and, hopefully, I’ll keep on learning.

“I could never have envisaged this when I made my debut. Other than the injuries I’ve had, it’s all been good. I’d been in the squad for a few games then we played Ross County at home on December 27 and I’d made the bench for the very first time.

“The next day I broke my leg at training and I was thinking: ‘What chance do I have?’ but I believe that made me hungrier. I came back and worked at stuff I was weak on and try to come back stronger.”

Life has changed immeasurably in many ways for Tierney in the two-and-a-half years since his debut against Dundee, and yet imperceptibly so in others. The trappings of fame and relative fortune haven’t changed him. His best friend now is the same one he had at nursery. It is still his family that he leans on in times of strife.

“My parents and my sister have always been there for me,” he said. “And every time I’ve been injured and come out of hospital my friend Jamie has come round to stay, kept me company and took my mind off it.

“I’ve had the same friends since the very start and I think that’s important.”

Like many of his peers, Tierney enjoys Playstation, UFC and loves attending gigs. That is one area where his celebrity has opened doors, with the singer Jake Bugg inviting both he and his mates backstage at his concert during the week.

“When I was growing up, I properly got into him and went to see him about three or four times,” he said. “For him to invite me to see him backstage was surreal. I can’t really get over it and I’ll never take it for granted, I know how lucky I am.

“[My friends] are all buzzing for front row seats and free tickets. It’s brilliant for them and anything I can do for my family is great, it’s changed everybody’s life and making everyone around me proud is the best thing.

“Jake’s a big Notts County fan so he’s grateful for what Callum McGregor did when he went down there.

“If I played him in the changing room it’d get turned off, I’m not sure if anyone would like it.

“It’s a different type of music, the rest of them are into different stuff to what I like, I like the Stone Roses, Oasis and Jake.”

After rhyming off such names as the mainstays of his playlists, Tierney rather surprisingly held his hands up for a quite shocking range of tunes that were heard emanating from the Celtic dressing room after the recent win over Hibs at Hampden.

“It was my CD,” he admitted proudly. “Whitney Houston and things like that. The boys love it, they always ask me to do the tunes after games, so I must be doing something right.

“I wasn’t born when the stuff was out, but my musical taste is brilliant, to be fair.”

That, may be open to debate. But one thing that can’t be questioned is the brilliance of the footballing talent he has shown since bursting onto the scene. He has already captained Scotland, for crying out loud.

“Things have happened so fast,” Tierney reflected.

“It’s everything I have always wanted, to play with Celtic and be known. It is what I have always worked for.

“Nothing is for free in life. I have worked that one out.”