Kieran Tierney: Celtic's rising star grounded by family

Tierney has made 25 appearances for Celtic this season

I've been sitting waiting on one of the plush, padded seats in the Celtic Park directors' box for 15 minutes, I check my watch again - he's late.

It's not uncommon. Questionable punctuality amongst footballers when reporters await is very much the norm.

The apology and the excuse that follows are most definitely not.

"Sorry," says 18-year-old Kieran Tierney. "I had to phone my mum and tell her I was going to be late home."

It's an unexpected start but family is a key theme in the intriguing chat that follows.

As he takes his seat opposite me and looks out with pride at his place of work, it soon becomes clear that the Celtic defender is a rare breed of teenager - thankful for what he's got and clear about why he is where he is.

Just a few months short of his 19th birthday, he find himself in the Scotland squad.

'The word is crazy'

Born on the Isle of Man, he moved to Motherwell as an infant - the Lanarkshire accent that flows, somewhat nervously, from a mouth brimming with teeth braces is unmistakeable.

"My mum told me about it - she had been checking the internet as the squad came out - I couldn't believe it," he said.

Tierney joins club mate Leigh Griffiths in the Scotland squad

"To jump straight from the under-19s to the full squad was unexpected but it's just about the experience and any game time will be a bonus."

International recognition caps a remarkable ascent since he made his first-team debut against St Johnstone in May last year.

Any notion of Tierney easing into life as a footballer has long since gone.

"I wouldn't know how to sum up the past year - the word is crazy," he says.

"Crazy how fast it has been. From last year playing under-20s football to this year playing European football has just been crazy."

Modern model footballer

He's been one of the main breakthrough success stories for Celtic under Ronny Deila - a genuine home-grown talent who has wrestled the left-back position from the seasoned international Emilio Iziguirre, and made it his own.

He's a dependable defender, a successful scrapper with a dash of finesse and the fans love him for it.

This modern-day local hero, though, has a modern-day story to tell about his trip to the top.

Makeshift games on the cobbled backstreets of tenement-lined towns have given way to 4G surfaces and regimented early morning rises.

Tierney is a product Celtic's football academy at St Ninian's High School in Kirkintilloch, where football and education live as one.

Tierney rivals Emilio Izaguirre for the left-back slot at Celtic

"I joined the school when I was 13," he explains. "I was getting up at 6am, doing training then all your school work and then having to train again at night.

"It was tough but a great experience - you're training twice a day and getting the best training in the country so it all benefits you.

"Everyone has the same chance at that age but it's not until you get older that some fade out of the game and get involved in the wrong things. For me, it's always been about the football."

The mother who received his earlier apology is one of the main reasons for his drive and determination.

When discussing football, he's as guarded as most current players - the press officer's steely stare behind me doesn't help - but there's a genuine freedom and warmth when he's talking about those closest to him.

A plain guy, with black boots

"I like to make my family proud when I go out there," he says looking out thoughtfully once again towards the Parkhead pitch.

"Obviously, it's great for me too but my family are all Celtic fans and they're all proud of me so that makes me happy.

"My dad drove me back and forward to training for years and my mum does absolutely everything for me."

Tierney may be a doubt for Scotland after picking an injury at Kilmarnock on Saturday

He won't entertain any notion of having it made it to the top though and there's a refreshing humility to his manner.

The surprisingly normal haircut, the lack of 'bling' and absence from the front pages appear to provide the evidence that he's so far dealt well with other distractions.

"I have always had the right people round me - my family and my real friends and they wanted me to do the right thing," he continues.

"So they were never going to lead me astray - I'm thankful for that and I wouldn't be where I am now if it wasn't for them.

"I've always been a pretty plain guy. People point to the fact that I wear black boots but that's always just the way I've been."

He definitely falls into the no-nonsense category.

To underline the point, it's not until he rises to leave that I notice he's been chatting away all this time in a club t-shirt as I shivered under a winter coat and scarf.

Mummy's boy indeed...