The qualifying for next season’s Champions League was always going to be arduous for Celtic. After relinquishing their Premiership crown to their cross-city rivals and thereby entering the preliminary rounds at an earlier stage – and avoiding the champions’ path altogether – this tilt at Europe will be the most challenging the Glasgow club have faced in a decade.

Rather than facing a title-winning team from one of Europe’s smaller leagues, as they usually would when the new campaign kicks off in earnest, this year Celtic will be facing off against opponents from countries of a similar stature to Scotland. Where previously the first round or two would normally see the Parkhead club given a relatively gentle introduction to continental football, now Ange Postecoglou will undergo a rigorous examination in his very first outing.

We know that when the draw takes place in Nyon this afternoon and the names are pulled out of the hat Celtic will be paired alongside one of Midtjylland of Denmark, Austrian runners-up Rapid Vienna or Turkish giants Galatasaray. It’s a long way from the likes of Estonian champions Nomme Kalju or Gibraltar’s Lincoln Red Imps.

Curiously, all three of Celtic’s potential opponents have visited these shores in the not-so-distant past after being drawn alongside Rangers in the Europa League. And as my colleague Graeme McGarry has pointed out within these very pages, any one of the triumvirate possess the quality and know-how to ask a helluva lot of uncomfortable questions and could conceivably send the Premiership runners-up tumbling down to the Europa League.

HeraldScotland:

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Such an outcome could prove disastrous in the long haul. For nine of the last ten seasons, the healthy bank balance in Glasgow’s east end had comfortably kept their domestic rivals at arm’s length. This wealth had long isolated the club from any legitimate challenge to their status as Scotland’s top club and history tells us that more than any other factor, a team’s wage bill is by far the most effective telling way to predict a final league position. Of course, that’s not how it panned out last season.

The loss of revenue from failing to qualify for the Champions League would be a blow in this sense, even if the club are not relying on a group-stage pay-out to balance the books. This unease would only be compounded if Rangers made it through the qualifiers and dined at Europe’s top table for the first time in over a decade as it would significantly narrow the gap in finances between the two rivals. Taking into account Steven Gerrard’s impressive work on the continent since arriving in Govan three years ago, it is a very distinct possibility.

Postecoglou will need to make a similarly quick impression. There is already a reluctance on the part of some supporters to throw their full backing behind the Australian; a skepticism around the 55-year-old’s suitability for the role due to his lack of coaching experience in Europe. Aside from a ten-month stint in Greece’s third tier back in 2009, Postecoglou has never managed in this part of the world.

Many of those who followed Postecoglou during his time in Japan with Yokohama F Marinos speak highly of the coach, though, and as far as I can tell he ticks a lot of boxes for what Celtic need from their new manager. He certainly looks like a more inspired choice to me than some of the other names linked with the vacancy during Celtic’s months-long hunt for Neil Lennon’s successor.

However, there’s one word that’s been bandied about in these various testimonials that should raise some concern. References to Postecoglou from those that know him have generally been glowing but you’ll struggle to find one that doesn’t contain vague allusions to a ‘process’. A new coach might well be shown patience from the stands at most clubs but time is a luxury afforded to few at Parkhead.

HeraldScotland:

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I do not envy Postecoglou. By all accounts, his teams function well and play progressive, attacking football once they get to grips with his system. The problem is that he will only have a few weeks to work with his players before these crucial games rear their head (remember, Postecoglou is still self-isolating) and even then, those weeks are far from ideal preparation.

New players will be arriving as the rebuilding work gets under way at Parkhead and there will be others heading for the exit too. It feels inevitable that Odsonne Edouard and Kristoffer Ajer will both be sold this summer, and there are perhaps one or two other important players that could be prised away. Then there’s the fact that the Celtic contingent in the Scotland squad – Greg Taylor, Jack Hendry, Callum McGregor, David Turnbull, Ryan Christie and James Forrest – won’t be with the first-team squad when they return to training on Friday due to their involvement at the Euros.

Postecoglou will want to have his players drilled and ready to go by the time the qualifiers roll around next month but the lack of training sessions with a full squad will be far from ideal. There are already a few sizeable holes in the starting XI needing plugged after loan players like Diego Laxalt, Jonjoe Kenny and Moi Elyounoussi returned to their parent clubs, and their replacements will need to be identified and recruited sooner rather than later if the Celtic boss is to field a strong team in Europe.

It is a mammoth task. It’s difficult to recall the last time Celtic went into these crucial early-season games in such a state of disarray and instability. The challenge on the pitch will be as great as it has been in a decade, and so too the financial imperative to qualify for the group stage if they are to maintain the economic gulf between themselves and Rangers. But within crisis lies opportunity, and it is now down to Postecoglou to seize his chance to make an instant impression.