Brendan Rodgers hails Celtic's '˜iron man' Kieran Tierney

Kieran Tierney has played 53 games for Celtic this season. Craig Foy/SNS

Tierney will play his 54th game when Brendan Rodgers’ men visit Motherwell this afternoon, with Forrest in line for his 53rd outing. These numbers are possible, says the Celtic manager, because the 20-year-old full-back is an “iron man” while his team-mate has added a certain steel to his efforts.

“What’s been brilliant for James is the consistency of his training,” Rodgers said of a player who has consigned to the past issues over his fitness. “I always say to the players here when they sign a contract, you’re signing a training contract. I’ll decide whether you play or not. The money is in your bank every month but you’re to work and get better. The great thing with James is he’s getting better every day – his goals, his assists, his consistency.

“Tierney now has games in his legs but you have to manage him slightly differently, especially on the back of the last couple of seasons where he’s had periods out. The cycle has been broken naturally because of injuries. But eventually they want to churn out game after game after and then you take them out for a little bit.

“[But he doesn’t want that] and that’s what he is. And there are boys like that – they don’t know what to do if you give them a rest.

“Some of the older ones, you give them a breather for the weekend, they head off to London or Paris or wherever. Tierney would go to the Celtic game. He’d come and stand in the corner. He understands the importance of games. It’s a delicate one in relation to getting games and consistency and maturity.

“Also what I think is important in the modern game is pushing young players over the hill. Actually letting them feel a little bit when they suffer. So they’re not all ‘oh, you’re not feeling right? Then let’s cut it back.’ They might be a bit stiff, so flush it out and get on with it. Tierney has a great mindset, though, a tough boy, and he’s unique because he’s not only quick but robust.

“Normally the boys who are really fast are prone to injuries with glutes, hamstrings, but he’s got mechanics which allow him to run at high speed and do it repetitively. He trains like a beast, and he plays like one. I demand all players train like they play and he definitely does.”

Stuart Armstrong is different. His five-minute appearance from the bench in the 3-2 win at Ibrox was his first since an operation on a troublesome hernia in January.

Having signed a one-year extension in August following protracted negotiations, Armstrong is again in the situation he was when discussions began on a new deal this time last year. Yet, because of his limited impact in this campaign, there has been little hoopla about the possibility of him running down his contract – which Celtic seek to avoid as it risks losing players for a fraction of their worth. Tom Rogic and Dedryck Boyata are in similar situations, but Rodgers appears sanguine about the potential for player turnover created by players entering the final 12 months of their deals.

“Time goes quick doesn’t it?” said the Celtic manager. “I have talked to Stuart briefly on it. I just want to help Stuart become the best player he can be. He knows what he has here, He knows the opportunity he has here and I know he respects that.

“So I don’t tend to get bogged down too much with that. I have a strong relationship with him. I know what he thinks and we will just look to continue developing him.

“I tend not to worry about that [final year of the contract juncture]. When I was younger I used to think it was personal, but it’s football. Players have short careers; of course, I’d love them to stay here but there are numerous reasons – on both sides as there could be issues with the club as well – that doesn’t allow them to sign.”