Shug is urging the veteran boss to take notice of decline that surrounds him amid his own errors in charge of a club about to implode

I thikn the principled decision that should have come from Martin O’Neill would have been to offer his resignation after his team’s defeat in Lisbon – and see if anyone had the manager’s best interests at heart.

Instead of their own self-preservation.

What more needs to happen, after the comprehensive defeat from Benfica in the Europa League, to prove to O’Neill he made a colossal misjudgement by returning to the club after winning a league-and-cup Double last term that enshrined his name in Celtic ’s history?

I have already written that Martin has lost the moral authority to continue in his post and added, with the deepest regret, that I can no longer take him seriously in a role in which he consistently exhibits errors of judgement in terms of team selection and game management.

If Martin has not been visited by moments of self-doubt amidst embarrassing beatings at European and domestic level then he has a conscience untroubled by factual evidence of decline all around him at Celtic Park.

How much more damage to his self-worth does he need to absorb before conceding that it looks as if things can only get worse for him?

It is no longer about O’Neill’s legacy at Celtic.

It is about his self-esteem not being given any hope of recovery because of a club that is on the verge of implosion.

Their problems will intensify if Hearts beat them this afternoon and put Martin’s side into third in the league.

The manager has to look about him and appreciate the fact that he, on top of his own personal deficiencies, is being let down by his employers.

Principal shareholder Dermot Desmond appears to have a financial, but not an emotional, investment in the club.

There is also, of a more practical nature, a poverty of choice when it comes to the players at O’Neill’s disposal.

Weakness is habitually punished in football.

If a strong Hearts squad underline Celtic’s vulnerability in front of a full house and live television audience, there will be an immediate negative reaction from fans already on the brink of insurrection. And if ever a team had a revenge motive, it’s the Tynecastle side who lost the league title on the same ground last May.

What summed up Celtic’s current mood was the fact that there was, among fearful fans, an acceptable level of defeat prior to the game in Lisbon.

When it gets to that stage, you know you’re in trouble.

None of this, incidentally, is about the memory of the Lisbon Lions and the failure to honour their name in the city forever synonymous with the greatest day in Hoops’ history.

For context, Celtic have, in their last three European ties lost, in no particular order, a three, a four and a five.

They have failed to make the Champions League, went out of the first domestic cup of the season to Rangers and their Premiership position comes under renewed threat today.

And we are still in October.

Greatness, in the form of a club from Scotland becoming the first from Britain to win the biggest European trophy, is preserved in perpetuity.

Infamy, in the form of a Celtic team unworthy of its illustrious predecessors being humbled in the same city is a close-up calamity that doesn’t diminish the treasured long ago and far away.

What it does do is bring the present day into sharp perspective and intensifies the scrutiny of a club that are in a glaringly obvious decline at all levels of business operation.

Celtic’s hierarchy has, of course, never knowingly overlooked a chance to make a bad situation 10 times worse.

In that spirit of consummate failure to read any room, the board will charge £35 for home ticket-scheme holders to watch Celtic play Celta Vigo.

Money has already been lifted from the bank accounts of the supporters concerned.

Whether the folks who are already 35 quid light actually go to the Europa League game, or not, is another matter.

The appetite for watching the team being flogged in public may be on the wane.

But, in typical Celtic fashion, the story gets even more complicated.

The Green Brigade and the Celtic Collective will give the match a miss. They object to having been called for everything in a club statement after tennis balls were thrown in the general direction of Desmond, in St Andrews a fortnight ago.

The identity of the person who did the name-calling in print is a source of mystery, since the document released to the media via Celtic’s social media platform was unsigned.

Animosity and anonymity have a long-established habit of going hand-in-hand when anything controversial happens at Celtic Park.

Just ask Brendan Rodgers.

To cut a relatively long story short, we are heading back to the days of Ronny Deila’s time as Celtic manager, when the top half of the stadium was closed on European nights due to a lack of public interest.

But, if that situation has arisen partly as a result of the Lisbon Liabilities having been dismantled by Benfica, what did anyone realistically expect?

The Portuguese club have twice been in the quarter-finals of the Champions League over the course of the last four years.

The noxious narrative at Celtic Park will, however, be one for a toxicologist if anything goes wrong against Hearts this afternoon.

But he was stumped for an answer when asked after the Benfica loss why a team who used to win Champions League matches can’t yet record a win in this season’s Europa League.

Starting to lose ground in their own country at the same time is unthinkable.

Time for reflection on the manager’s part. Again.