There once was a time when the transfer market stirred a lingering anxiety in Celtic fans.

Sleepless nights as big clubs circled around their heroes, endless refreshing of social media as protracted pursuits of targets dragged on and on. However, like he has with so many things, Ange Postecoglou is changing all that.

It all started as the January 2022 window approached. Billed as pivotal to ambitions of reclaiming the Premiership title with Rangers six points clear at the summit, Celtic desperately needed reinforcements to bolster a group toiling under the weight of a quite freakish spate of injuries.

Matchday squads were frequently filled with wide-eyed academy hopefuls as the winter break approached; drafted in, if for nothing else, to ensure there were no empty seats on the bench. Postecoglou had already worked through a busy summer, one always bound to be fraught given the turnover of talent at Celtic Park.

Where Scott Brown, Odsonne Edouard, Kristoffer Ajer and Ryan Christie moved on, in came the likes of Kyogo Furuhashi, Joe Hart, Carl Starfelt, Jota, Josip Juranovic and, at the very death, Cameron Carter-Vickers. That so many hit the ground at full pelt immediately suggested the new manager knew what he was doing with this transfer lark, but the importance of January could not be understated.

Or, more specifically, the importance of a rapid January could not be understated. The clock had barely struck midnight on Hogmanay before Celtic had Daizen Maeda, Reo Hatate and Matt O’Riley in the door. No sagas, no deadline day scrambles, just some shrewd business which had no small say in the destination of last season’s title.

Acquired for bargain fees, they were arrivals stark in contrast to the hefty sums spent on expensive missteps such as Vasilis Barkas or Albian Ajeti just a year prior. And so it set a tone: Celtic were delivering what Postecoglou wanted and his judgement was being proven right more often that not.

Drafting in free agent Aaron Mooy didn’t do much to set pulses racing last summer, and now he’s arguably the most in-form player in the country. Postecoglou has earned the trust of supporters, and the club’s hierarchy, when it comes to identifying talent.

But he’s also been setting a foundation for something else, something that’s generally a much harder sell. Celtic fans are no strangers to bidding farewell to their top stars – it’s been an integral part of the club’s business model for years.

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At times, however, acceptance of this has been more than a bit grudging. Maybe it was uncertainty over whether they would be adequately replaced, perhaps it was difficult accepting that financially Celtic cannot always compete with even the Premier League’s lesser lights, or that the timing was simply off – even lifelong fan Kieran Tierney did not depart for Arsenal without experiencing a degree of hostility.

So, when Postecoglou openly told fans back in October that they should expect to see players leave before they’re ready to bid them farewell, he was taking somewhat of a risk. Being ‘agile’ in the market was the manager’s sentiment, one he probably would not have expressed had he not already laid that aforementioned foundation – Postecoglou could afford to be so straight with supporters because they trust that everything he does is part of a plan.

It was surely a contributing factor as to why the departures of Josip Juranovic and Giorgos Giakoumakis last month barely prompted much more than a collective shrug. Alistair Johnston had been recruited well ahead of Juranovic leaving, and Hyeun-Gu Oh was announced in advance of Giakoumakis being unveiled at Atlanta United.

It’s also why news from much-trusted transfer journalist Fabrizio Romano on Tuesday that Premier League clubs may be circling around Carl Starfelt won’t invoke too much fretting either. If he does go, and that obviously remains an considerable ‘if’, then it is simply Postecoglou’s transfer plan in action again.

Among the manager’s top priorities is to mould Celtic into a competitive Champions League club, comparable perhaps to the likes of Ajax. The Dutch champions are famed for being a consistent continental presence, despite their budget being a comparative fraction of clubs in England and elsewhere.

But it’s easy to forget that the price they pay for this is having their squad near-dismantled every few years. After Erik ten Hag led them to a Champions League semi-final in 2018/19 – humiliating Real Madrid along the way – they were forced to reckon with the loss of Frenkie de Jong, Matthijs de Ligt and Kasper Dolberg in the ensuing summer market, before Hakim Ziyech and Donny van de Beek followed them out the door a year later.

In that same timeframe, however, they signed Lisandro Martinez, Antony, Edson Alvarez and Mohammed Kudus. The former two have already banked Ajax in excess of £140m, while the latter pair will almost certainly go for a combined nine-figure sum.

Of course, Celtic are nowhere near operating on this lofty financial plain, but the principles remain the same: efficient, effective recruitment, followed by selling at the right time, and for a profit that can be reinvested. In the era of football’s mega-rich, this is the way of the world for clubs of Celtic’s stature.

They have always been adept at banking big bucks for players down the years, but their transfer process as a whole has not always been so efficient, with there arguably being as many as misses as hits down the years.

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It may yet take some time before Celtic become a serious proposition at Europe’s top table, but the speed with which Postecoglou has streamlined their signing strategy has been impressive. The downside, if there really is one, for Celtic is that it will only continue to enhance his managerial reputation.

His name is never far away from vacancies down south these days, but he appears in absolutely no hurry to abandon his Parkhead project. And why would he be? The club are giving him everything he needs to succeed, results on the pitch are near-flawless, and he has the adulation of a global fanbase underpinning everything he does.

Postecoglou’s work in the transfer market is no small factor in ensuring the above. He has removed almost all the stress and strain from a process which can often be arduous for supporters, and teed the club with a recruitment model they can utilise for years to come, long after his time in Glasgow comes to an end.