As far as Celtic’s signing business goes, Ange Postecoglou hasn’t been a man to muck about.

He does, however, agree that navigating the transfer window is a bit like a high-stakes game of Jenga. The Parkhead manager is only ever one irrefusable sum of money away from one of his top players being prised away by a richer club, and it’s his job to make sure that pieces being removed from what he has built in Glasgow doesn’t cause the whole thing to come crashing down.

For that, he needs to stay one step ahead. And, to his credit, Postecoglou has yet to really be caught out by an unprepared-for departure. When Josip Juranovic and Giorgos Giakoumakis exited stage left back in January, Alistair Johnston and Oh Hyeon-Gyu were already in place to ensure the house that Ange built remained structurally sound.

This summer, he expects Celtic will be tested more than ever before under his leadership by incoming offers, but is confident the plans already in motion will ensure yet more seamless transitions, if required.

“It’s not a precise science,” he explained. “I was trying to be predictive with the January window. We kind of knew Jura and Giakoumakis would go. We are losing two very good players who had contributed greatly to our success.

“But was at an opportunity to bring in a couple of younger players who might have a higher ceiling? You don’t know, but the opportunity was there.

“We thought Oh and Alistair both already looked like good players, they are younger than the guys who left, so potentially could have a higher ceiling if we got it right.

“That’s always the challenge. This is the probably first window where we’ll really get tested on some of our key players by other clubs.

“Our planning is in place, so if that happens, it’s like the Jenga puzzle, before it all collapses we’ll hopefully already have a piece in place to ensure you can take one out and still build strong.

“I like that Jenga analogy!”

Postecoglou cites constructing something long-lasting as part of what he most enjoys about management, last week pointing out that he has never arrived at a club where things were already rosy. Challenging that may be, but it has given the 57-year-old ample opportunity to shape a team in his image.

He has made no secret of the fact that the Champions League – and being there consistently – is what is required to take Celtic to the next level of his plan.

“It’s more than investment,” said Postecoglou. “There are plenty of examples where investment alone is not the answer.

“It’s not just here, it’s anywhere. It’s about how you’re investing and why you’re investing.

READ MORE: Carl Starfelt says snap judgements on Celtic team-mate are 'not fair'

“I’ve said in the past this club needs to play Champions League football on a consistent basis, and being in the position where every year – if all the stars align – they can make an impact at that level. That’s not going to happen every year, it might be every three or four.

“But you’ve got to be there chipping away and improving every year. Every time a player leaves you have to try and get a player who is hopefully a better version so you can constantly chip away.

“Hopefully, by being in the Champions League every year, revenues would increase which gives you an opportunity to then look at a different quality of player. It’s that consistency of not getting too bogged down on just…you’ve got to win the league here to get in the Champions League, that’s your bread and butter.

“But you can’t just have that as your end point, it’s got to be ‘that’ because it gives you ‘this’. You don’t dismiss the Premiership, you don’t just say ‘we want to be champions’.

“You want to be champions to give you an opportunity to go into a space where you can be really challenged, and that’s where your growth happens. If it’s just about being champions for being champions, this club’s got a long, long history of doing that.

“You’ve seen it in the past with Martin O’Neill reaching a European final or at times getting out of the group stage, the growth comes by being consistently in there.”

Having had a year to sample what European football’s top table demands of you, and another season of domestic success under their belt, Postecoglou is in no doubt Celtic are a better team than this time 12 months ago. But the key is not to stand still.

Celtic fans will, understandably, have concerns that some of their favourites may be tempted elsewhere by the time the new season arrives, but there’s no evidence currently to suggest that those who might come in as replacements can’t take the team to another level once more.

READ MORE: Albian Ajeti makes Celtic return as Sturm Graz confirm no deal

And then there’s those who are already in the building and perhaps won’t have obscene money thrown at them during the summer, players Postecoglou believes can continue to improve the collective from within.

“We just have to be stronger than we were last year,” he insisted. “I’m sitting here just now and, hand on heart and without the bias of me being the manager, I think we’re a better side than we were 12 months ago. We needed to be to achieve what we have so far.

“That’s got to be the goal next year, to be sitting here saying we are a better team. That doesn’t mean winning the league by 30 points, it may still be a narrow margin, but your football, the way you’re playing, the development of your players has gone to another level.

“Whether it’s transfers this window, we just want to build a better, stronger squad and be a better team than we were last year. Some of it will be natural because some of the players are still developing.

“In terms of transfers and what we want to try and do, that’s our focus.”