AS ever when a Scottish side crashes out of Europe, the inquest and the blame game aren’t far behind. Particularly when it is an unexpected exit like the one Celtic suffered at the hands of CFR Cluj on Wednesday night, although some may disagree with that assessment.

So, where does the responsibility lie for the crushing blow that the Scottish champions suffered as they drop out at the third qualifying round in Europe’s elite competition for the second year in a row? And arguably, against a team they should be beating quite comfortably for the second year in a row? There is plenty of culpability to be shared around.

The ire of many Celtic supporters has, with some real justification, been aimed at the board since the final whistle at Celtic Park. But while there is little doubt that the recruitment strategy more than played its part in Celtic’s Champions League exit, and the seeds of Celtic’s downfall were sown long before matchday, the decisions taken on the night by manager Neil Lennon and ultimately, his players, were equally responsible for the shambolic nature of the performance.

The first and most glaring of these missteps was to name perhaps the best midfielder in Scotland and one of Celtic’s most influential performers at left-back, with Callum McGregor shoehorned into a position he was entirely uncomfortable with.

The fact that Lennon felt unable to trust his £3m signing Boli Bolingoli to perform any better than the makeshift full-back is a damning indictment on how he views the Belgian. Christopher Jullien too, the £7m centre-half that was brought in from Toulouse, wasn’t trusted to take his place in a defence that ultimately went on to lose four goals at home.

In the case of Bolingoli, the decision to remove him from the firing line was perhaps one that had some logic behind it given his indifferent start to life at Celtic, but only if there was a natural replacement to come in and take his place. Alas, none exists within the squad.

Even Jonny Hayes may have sufficed as a stand-in, because that would have at least maintained McGregor’s position at the heart of midfield and would have avoided the disruptive effect that the reshuffle ultimately had throughout the entire side.

And the most frustrating thing perhaps from the point of view of the Celtic supporters is that it wasn’t as if Lennon hadn’t been warned. After all, his predecessor Brendan Rodgers had plumped for precisely the same set-up when Celtic fell to an abject defeat to Rangers in December, with Olivier Ntcham and Scott Brown manning the midfield as McGregor was marooned out wide.

The result, predictably, was the same, with Celtic struggling to retain possession in midfield without McGregor acting as their lynchpin. It was no coincidence that Brown had his poorest 90 minutes since that day at Ibrox, while Ntcham – who was undoubtedly better - often wanted too much time against the high-pressing opposition.

Having made the error, Lennon compounded his mistake by not correcting it, when everyone inside Celtic Park could see that it wasn't working. Cluj were hardly reinventing the wheel. Their main tactic was to fire diagonal balls in behind McGregor to their winger Ciprian Deac, who in turn would inevitably get service into the area. Or worse, take up a position where he could easily win the ball in the air and threaten the Celtic goal.

The home side even got a warning shot as Deac fluffed his lines as he ran onto a cross over McGregor’s head, before the same ploy yielded their first goal as he made a surer connection second time around.

Lennon does deserve credit for getting after his players at the interval and making sure they stepped things up in the second half in terms of their intensity and aggression, leading to them becoming a far greater threat and getting the three goals that really should have seen them through, but the naivety that was evident in their play undid all that good work.

Twice they held the lead on the night, and twice they threw it away, as Lennon and his players failed to shut up shop and snuff out the one-dimensional threat posed by the Romanians. There was inaction from the bench in these moments, with substitutes being made only when Celtic were chasing the game. And wouldn’t Scott Sinclair perhaps have been a better option to turn to when the situation turned dire, rather than Lewis Morgan? But the more experienced winger was nowhere to be seen.

There was also a lack of in-game intelligence shown by the men in green and white themselves. For all of the experienced players out there, no one had the wherewithal to grab their teammates by the scruff of the neck and drag them over the line. Still the full-backs bombed forward, and still Celtic were wide open.

No one has to tell captain Brown that it was he who was more culpable than anyone else on the field for Celtic, not only failing to take on that responsibility, but capping off a night to forget with his moment of madness that cost his side a penalty and a crucial goal.

The men in the boardroom, in the dugout and ultimately on the field must all shoulder their own burden of responsibility, while the fans pay the price for their collective ineptitude.