When it comes to the officiating he has witnessed upon his return to Scotland this season, there has at least been one consistency that Brendan Rodgers can rely upon. The Celtic manager has consistently been left tearing his hair out.

There has been another constant during this campaign mind you which has impacted upon his side’s chances of success, in that some crisis or another has seldom seemed far away, but the latest – one that has resulted in him being hauled before the Scottish FA to explain himself – is rooted in his frustration at the inconsistency of refereeing.

Rodgers unleashed both barrels at John Beaton for the role he played from the VAR HQ at Clydesdale House in Celtic’s defeat to Hearts last weekend, but his ire is not limited to just one refereeing performance or the single official he saw fit to comment on so strongly.

Rather, Beaton’s bungling – in his view - was the straw that broke the camel’s back.

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The sending off of Yang Hyun-jun would have been bad enough when judged as a standalone incident in Rodgers’ book, but in the context of the unpunished high boot that Celtic defender Liam Scales took to the face the weekend prior from Motherwell’s Theo Bair, he found it baffling.

But not quite as baffling as the view from the officials at Tynecastle that Yang’s studs had made contact with Hearts defender Alex Cochrane’s face.

“That was in the match report, and that’s two days later,” Rodgers said.

“I think everyone’s view, not just mine, if you watch it, then clearly he didn’t do that. I think he brushed his shoulder. But he certainly didn’t have his studs or boot in the face.

“The interpretation of it is the difference, from game to game and referee to referee. If you look at our incident where Yang gets sent off, what happens if Liam Scales goes down the week before and starts rolling about holding his face? Maybe because he stood up, was honest and just took it, nothing happened.

“I understand players are cute - players are clever - and you want them to be that. That’s the game, they need to deceive, they need to be clever. That’s what you do.

“But, especially when you now have cameras to see it and observe it, then you expect it to be seen. Like I said, Don Robertson made the right choice in the game.”

And as for the handball that Tomoki Iwata was penalised for to give Hearts the chance to open the scoring from the penalty spot, it inspired the sort of reaction from Rodgers he has become all too regrettably familiar with this term.

“I’ve got to be honest, I’ve been stood on the touchline more times than not this year with my head in my hands just with things that I see,” he said.

“I’ve never been like this in football, but I see the time element, the nonsense of looking at a penalty whenever a move is offside, it’s totally irrelevant if it’s offside, and we’ve seen that a few times in a few of the games.

“The game just feels as though it’s slowing up. The whole intensity, the whole tempo, the whole feeling of a game.

“It just seems to be being refereed outside of the game, and I think that is the big concern.

“I only talked openly and honestly about what I seen in the game, and it was that one game.

“All we look for as coaches and managers is consistency in decisions, and I think that the first one, the on-field referee made the correct decision. He gave a yellow card, I think that’s what it was.

“We’ve had incidents prior to that. I obviously watch football day and night, so I see the challenge on Liam Scales the week before against Motherwell where there’s no card. I see Connor Goldson’s straight leg on the Livingston defender and it’s a goal. So, I see that, and I see nothing [gets done].

“Then, our guy, who doesn’t touch anyone’s face with his studs…now admittedly it was high, but it wasn’t reckless, it wasn’t forceful, it’s a yellow card.

“I think that is a part of the frustrations that you have of course [the inconsistencies].

“I respect the job is a difficult job, so for me to come out and question it, it really takes something. Because it’s not something I do, I tend to look purely at the football aspect.

“We were ok with 10 men, we have a plan always in how we play with 10 men, then the penalty just before half time then puts a different feeling and different emotion in the game.

“Then of course Hearts don’t need to chase the game, they are winning the game 1-0.

“So, I felt the decisions were pivotal in the game, and like I said, I never tend to look at that so much, even things that have gone good or bad against us.

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“I tend to look at the football aspect, and I felt we started the game well, but the decisions that were made were pivotal in the result.”

What is even more worrying for Rodgers is that the team of on-pitch referee Robertson and VAR Beaton are supposed to be two of Scotland’s most senior and experienced referees.

“It was a big game and that’s clearly why they were on it,” he said.

“So, you want the big decisions to be right. I honestly didn’t think they were.

“They had big consequences but they weren’t really big decisions when you know the referee has got it right on the pitch.

“Anyone who knows football will look at the penalty and think there’s no way on earth it’s a penalty.

“That’s the frustration and emotion that you guys don’t feel. That was something that was pivotal.”

Rodgers hopes there won’t be any further refereeing controversies when his team return to action tomorrow in a home Scottish Cup tie against Livingston, with the chance of a league and cup double still very much up for grabs despite the difficulties Celtic have faced this season.

“It’s certainly been the most challenging season as a manager that I’ve had, but that’s all part of it,” he said.

“I think it’s the football aspect that I love, and that’s the bit that I really enjoy.

“Of course, the other stuff that comes with it is part of the territory when you’re at a big club, but it’s all a part of the modern game.”