CELTIC could hardly have picked a worse time to lose some of their relevance in continental football. Like major powers carving up the map of the developing world in the early part of the 20th century, Europe’s big clubs – led by European Club Association supremo Andrea Agnelli of Juventus – are currently marking out their territory for the future of the sport.

I say hardly, because assuming the Italian gets his way and a version of his plans for eight-team groups, the top six of which retain their place for the following season, are adopted, a worse time for a result like this to come along would be the 2023-24 season. Fail to reach the Champions League then, and the Scottish Champions may never return.

You will read much in the next few days about how Celtic - or the Scottish champions whoever they are – are really a Europa League club these days rather than a Champions League club. True, they were hardly in the mix to win the thing outright, but I’m not really sure what this means. Or whether this is a productive way of looking at it.

The Herald:

READ MORE: Ex-Celtic striker Andy Walker: Leaving £10m of talent on bench makes no sense

Leave aside Ajax, who famously made it all the way to the dying seconds of the competition’s semi-final last season, cuffing Real Madrid and Juventus to get that far, but this is a competition where Viktoria Plzen took seven points last year and the likes of Red Star Belgrade and Young Boys took four. With a turnover of £59m and 60,000 crowds which are the envy of many in Europe, of course clubs of the scale of Celtic should aspire to that level.

By whichever of Uefa’s measuring sticks you care to use, Celtic should have had this one in the bag. Their individual co-efficient dwarfed that of Cluj, who tumbled in the Europa League play-off round last season to little FC Dudelange of Luxembourg. Even the much-maligned Scottish league, swollen by the efforts of Celtic and Rangers in Europe last season, is ranked nine spots higher than its Romanian counterpart.

For a one-off blip, matches like these come about far too often for Celtic, not to mention other Scottish clubs. Okay, so these matches come at a precarious moment, when they are still assembling their squads, but in the last five years then Parkhead side have lost in these matches to Maribor, Malmo, AEK Athens and now CFR Cluj. Even on their good years under Brendan Rodgers, they got the better of an equally frantic 5-4 aggregate victory against Hapoel Be’er Sheva in 2016-17 and squeaked a 1-0 aggregate win against Rosenborg the year later.

So what exactly went wrong this time? Well, firstly give some credit to Cluj - a side who are rebuilding their own relevance after a recent insolvency event, even if many of their players are approaching veteran status in a team where the average age was touching 30. If anything, that helped them to deal with their febrile surroundings in the East End of Glasgow, while Dan Petrescu did another number on Scottish teams after his heroics with Unirea Urziceni.

The Herald:

READ MORE: Listen: Where did it all go wrong for Celtic against Cluj?

But it isn’t hard to pick holes in how Celtic approached these matches. A kind of soccer scattergun is in play this morning, which sees blame being sprayed around all over the place, and Neil Lennon correct to admit that the fault lay ‘collectively’.

It has been difficult for Celtic this summer with managers and recruitment chiefs coming and going but the bottom line is that the Parkhead side ultimately couldn’t trust Christopher Jullien and Boli Bolingoli, two players purchased to the tune of £10m this summer, in a game of this magnitude. While I have only seen both once over 90 minutes in the flesh, during the 5-2 win against Motherwell on Saturday, I wouldn’t argue too much with Neil Lennon on that call. While it is too early to write these guys off, for For all his size and bulk Jullien seems laboured in his movement, while pitching the attack minded Bolingoli into action would also have gone down as a risk.

The Northern Irishman also stands accused of pitching Callum McGregor into action at left back, something that wasn’t particularly successful for his predecessor Brendan Rodgers in the December Old Firm match. Fair enough, but he still had a hand in one goal and most of those same critics would agree that they couldn’t play Bolingoli either.

For me, Celtic’s fault was far simpler than that. You could tell within the first 10 minutes of the first game out in Romania that this tie was too wide open. At times, when Celtic had a winning position, they could have done with being more circumspect, more prepared to sit in and hit on the counter. As much as the manager picks the tactics, that is a failing which equally applied to Brendan Rodgers’ side and the players themselves must carry the can, not least individual mistakes such as Scott Brown’s bizarre handball and Scott Bain not getting a firmer wrist to the ball in the lead-up to the killer third goal.

As for the board, well Peter Lawwell once said that selling a player was required to offset the losses of failing to reach the Champions League. At least Celtic have already achieved that in the form of Kieran Tierney’s £25m departure to Arsenal. Getting that all tied up before a Champions League exit which might have ratcheted the pressure up for a cut price sale, seems ever more like a clever bit of business.