Cup draws are always riddled with conspiracy theories and the old chestnut, “there are a couple of warm ba’s in the bag”, tends to do more rounds than the actual competition itself. Yesterday, in the bowels of Hampden for the William Hill Scottish Cup fourth round guddle in the pokes, the said balls must have been generating a fair old heat as a trio of Scottish Fire & Rescue units came honking and hooting into the national stadium to deal with a potential incident.

It was a false alarm, of course, but perhaps they were taking precautionary measures as Celtic youngster Kieran Tierney was in the vicinity. The 18-year-old has been on fire of late, after all. Predictably, the salivating scribblers in the Scottish media have feverishly worked themselves to the point of self-combustion with their praise and plaudits. John Collins, the Celtic assistant manager, fanned these flames recently be declaring that Tierney was playing like a “£5 million full back.” It seems this particular Bhoy from the Isle of Man is becoming, well, a man in the rough and tumble of Scottish football.

Amid the hype and hysteria, Tierney is keeping his feet firmly on the ground. The day-to-day duties at Parkhead ensure he won’t be getting carried away. “The youngest people have to clean the boots, so if I’m the youngest there I have to clean the boots and get the balls,” said Tierney, after watching Celtic get a fourth round trip down the road to Stranraer. “That’s all good for me. I’m still in the youth team dressing room, so I need to keep working hard and hopefully one day I can be in the first team dressing room. I’m training with the first team every day and I trained with them last season. I’m there all the time and talking to them all and getting involved in everything they do, so that’s good.

“It (the £5 million remark) is obviously a compliment you take well but I don’t want to get too ahead of myself. It’s good for him (Collins) to come out and say that and it doesn’t get said a lot about young people. I was surprised by it when I first saw it, I didn’t expect it and it was actually my dad who showed me. None of my team-mates have mentioned it but I’m sure they will now. It’s all still hard to take in for me. I just see myself as still being a Celtic fan. But it’s brilliant for me and I just need to appreciate every moment I have with the first team and make the most of it.”

Having racked up 10 first team appearances, both on the home front and in the European theatre, the raw recruit has certainly seized his opportunity to make an impact.

There won’t be any more forays on the European stage, with Celtic now out of the Europa League, but Tierney is focussing on the domestic scene and trying to help the Glasgow club win a treble. “That is the aim for everyone at Celtic,” he declared.

It’s an old cliché – and where would fitba’ be without clichés? – but Tierney is “living the dream.” A few years ago, he was the ball boy at Parkhead during one of those giddy European nights and now he’s hoping to trot out at Hampden Park as a player in a cup final having been parked in the stands a few times as a supporter.

“Every team wants to get there,” he said. “I’ve been to all the Celtic cup finals since I was young. My dad used to take me so I’ve got a lot of experience of cup finals as a supporter anyway. We’ve won a few when I was there, I remember Darren O’Dea scoring the winner in the League Cup Final (in 2009). Hopefully my memories can be similar to the ones I went to and we can win it.”

Making the step up to the rigours of first-team duty can be a robust challenge in many ways but Tierney has adapted to the physical demands and Ronny Deila, the Celtic manager, has been impressed by the teenager’s roll-up-the-sleeves approach. “That’s one of my main things, my work-rate and my work ethic and it’s good that he’s recognised that,” added Tierney. “I played against Ajax on Thursday and then played in Inverness on Sunday. It was hard for me but I played the 90 minutes in Inverness and that was good for my fitness. I’ve now completed four or five 90 minutes for the first team. My legs tire towards the end of the game but it’s getting better. I have supported Celtic all my life and I’ve worked so hard to play for them.”

That hard graft continues to reap rewards.