"I am not going to change my approach."

The words of Celtic boss Ange Postecoglou in the post-match briefing after a 4-0 hammering at home in the Europa League by Bayer Leverkusen. The defeat sent his side tumbling to the bottom of Group G and left the Glasgow side behind the 8-ball after just two games of a six-game qualifying campaign.

Ange's men have also conceded eight goals over those two Europa League matches after an opening day 4-3 loss to Real Betis in Seville. Worryingly Celtic supporters were also heading for the exit signs long before the Bayer Leverkusen match ended. Apathy and boredom had long set in. It is not a good look.

Now here's another quote: "The definition of insanity is doing the same thing over and over again and expecting a different result."

These words are usually credited to the acclaimed genius Albert Einstein. An acclaimed managerial genius Ange is certainly not ... yet.

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Celtic have won just two matches out of their last eight in all competitions, both of those victories coming against Ross County and Raith Rovers. The Aussie once again steadfastly refused to change his style or philosophy and alter his football principles on Thursday night against a team who trail Bayern Munich in the Bundesliga by just three points at this juncture.

One thing that is clear for the Celtic supporters is that the style of football Ange has implemented at the club is not working ... yet. Results alone tell you that.

The inverted full-backs, playing the ball around at the back, fast-tempo attacking football? It's just not happening for Celtic ... yet.

If Celtic don't have the personnel to carry out the manager's instructions, then would you think that some kind of adaptation would be needed. Not Ange. However, continually losing football matches has a shelf life at a club like Celtic especially amongst the hierarchy and the supporters.

If the Celtic players are incapable of doing the job that Ange is telling them to do then why does the manager ask them to do it in the first place? That is why Ange's 'my way or the highway' could ultimately become his undoing.

This leads us neatly back to Albert Einstein. There is also a school of thought percolating among the Celtic supporters that Ange is now being stubborn by refusing to embrace pragmatism when it is required. Another criticism is that he has no Plan B or that his Plan B is to simply make Plan A better. Who is this Albert Einstein character anyway?

Celtic remain one of the few clubs in world football whose supporters continually blame the board for every single match that is lost and a result that does not go their way. It's their default position - don't blame the manager, blame the board.

But questions can't be held in stasis forever. Is Ange deploying his players in the right way? Is he getting a proper tune out of what he has in terms of player personnel? The answer to both of those questions would have to be a resounding no.

Results, style, philosophy, team formations are always on the manager. Ange will ultimately carry the can for what happens in the football park every 90 minutes, not the suits.

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In the manager's defence what you can also say is that he is still in some sort of football limbo when it comes to enjoying the full backing of the Celtic board. He still has no managerial assistant, no DOF, or a bonafide CEO to work alongside. It truly is a shocking state of affairs for a club like Celtic. It must also be a massive source of frustration for Ange.

In that sense, most Celtic fans will possess a huge degree of sympathy for him. There have also been social media rumours circulating this week over Ange's future with Gordon Strachan's mooted as a ready-made replacement. Such conjecture is unwelcome, and it filters through to managers and players. At its worst that can create a wholly toxic and unworkable atmosphere.

The Celtic hierarchy should do the Aussie a favour by nailing that speculation to the wall once and for all. Why don't the Celtic board make a public declaration that Ange is their man and that they will support him 100 per cent and arm him with every tool at their disposal to wrestle the title back from Rangers this season? After all, there is the small matter of £40 million Champions League money resting on it.

It might be an uncomfortable or awkward truth that the Celtic board don't want to confront. Do the Celtic hierarchy deep down believe ​that Ange is out of his managerial depth? Are the Celtic board actually setting Ange up to fail? Do they trust Ange enough to give him another transfer window and cash to splash on players in January?

Current results certainly aren't helping Ange's cause, but you get the feeling that the board could well be hedging their bets on this one.

READ MORE: Ange Postecoglou has faith in the Celtic 'process' as boss refuses to budge on principles - points from the presser

Celtic head to Aberdeen on Sunday to face a Reds team utterly bereft of confidence. However Celtic are just as bereft themselves. If you don't believe me check the 'W' column.

They will also have the small matter of lining up against former Captain, Leader, Legend - Scott Brown. It's a wonderful sub-plot in a season that has already had many twists and turns and we still haven't donned a Hallowe'en mask. Must win games in October were most certainly not on Ange's, the supporters' or the Celtic board's agenda.

Bayer Leverkusen was a class apart and in truth, any kind of positive result would have been wishful thinking on Celtic's part. Pittodrie, Fir Park, and Easter Road all lie in wait for Celtic before the month's end.

Every one of those fixtures has strayed into the must-win category. The pressure is already on the gaffer and his men to deliver.

The pro-Ange brigade is keeping the faith and trusting the process for the time being. However, Celtic's domestic results especially away from home need to drastically improve.

If they don't then it doesn't take a genius like Albert Einstein to work out that either Ange or the Celtic board will be forced to 'change their approach' moving forward.