The league title has already been sealed. But the season is far from over.

Wednesday night’s 4-2 defeat at Easter Road was Celtic’s third match in a row where they failed to register a victory, following on from a chastening 3-0 loss at Ibrox and a 2-2 draw at home to St Mirren where Ange Postecoglou’s were fortunate to escape with a point – a concerning run, given there is still the small matter of a Scottish Cup final against Inverness to contend with a week tomorrow.

The drop-off in form has sparked one or two niggling doubts in the back of some supporters’ minds as Postecoglou’s ‘we never stop’ mantra has been put to the test in recent weeks. There is still a final cinch Premiership fixture against Aberdeen tomorrow afternoon, and a win would go a long way to assuaging that apprehension.

For Callum McGregor, though, context is everything. The Parkhead captain accepts that he and his team-mates haven’t hit the required levels in their past three outings but he insists that there are one or two mitigating factors that must be taken into account.

Injuries to the likes of Cameron Carter-Vickers, Alastair Johnston and Greg Taylor have forced Postecoglou’s hand when it comes to his selection, while other players who have found themselves on the fringes of the first team this term have been given an opportunity to stake their place for spot in the starting XI. None can say they have given their manager much food for thought.

McGregor has been around for long enough to know that dips in form happen, though, particularly when the team finds itself competing in essentially meaningless games – which is precisely why the Scotland internationalist won’t be losing any sleep over Celtic’s three-game winless streak.

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“No, you have to put it into context,” he said. “If anyone is trying to pick holes in the group for whatever reason, you just have to look at what we did up to winning the title. It’s been outstanding, very minimal mistakes and hardly any dropped points.

“There have been massive winning streaks, we shown hunger, desire, everything. So of course we are disappointed with the post-split fixtures and results. We haven’t reached that level. But up until becoming champions, we were outstanding.

“So it’s difficult to be hard on the group. Yes, we want to maintain as high a standard as possible but sometimes in football it doesn’t quite work like that.

“Performance levels just need to get better. We have dipped a little bit, whether that’s physically being a little bit tired or the demands that the run took out of the team. When the objective is complete, it’s maybe human nature that you subconsciously take a little bit of a step back.

“There is always a fight to stay on the edge as a professional footballer. You are judged on playing on the edge and you always fight to improve and get better.

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“Maybe there is a bit of that and the physical stuff. For sure, we haven’t reached the performance levels in the last three games - and it’s up to us to fix it.

“Again, there needs to be context in terms of the team being chopped and changed, compared to where we have been when we won the title. But the main thing is we remember the feeling of disappointment and we don’t just disregard it.

“We don’t just say, ‘We are champions and who cares?’ That’s not the mentality of this group. We need to remember how it feels when we lose - firstly for a final that we want to win.

“And secondly, for next season when we don’t want give teams any oxygen in how they play against us and get confidence. We have to harness this feeling as much as we do when we win.

“You have keep that with you and minimise how many times you feel like this. But we have a real chance to celebrate on Saturday and hopefully that will give everyone a lift.”

Postecoglou was keen to shoulder the blame for Wednesday night’s disappointment in Leith, admitting that his chopping and changing might well have led to a disjointed performance.

McGregor accepts that shuffling the pack might well have disrupted the champion’s rhythm but he also firmly believes that the players out on the park should be doing better, pointing to the fact that his team-mates have slotted in as required throughout the campaign without allowing standards to slip.

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“The boys who have come in have probably not had enough game-time to be match sharp,” he explained. “But we train at a certain intensity every day and everyone understands how we want to play.

“A lot of what has been good this season is boys doing very well when they have come in. It’s just a case of some players having a wee bit of limited game-time from the start and some fitness issues. But whatever team we send out on the pitch, we have to look and act like a Celtic team.

“To be honest, I don’t think we did that - we didn’t cover ourselves in glory. The first half was good but then we let them back into the game. Then we didn’t deal well with going down to 10 men.

“So as much as the manager says he takes responsibility for the changes, we need to take it as players as well.”

It is perhaps a telling sign of what life is like in Glasgow’s goldfish bowl that Celtic have already won the Viaplay Cup and the league title, and are on the brink of yet another treble, yet there is still some dissatisfaction from fans over the team’s last three games.

For those who are relatively new additions to Postecoglou’s squad, it is a gentle reminder of how quickly things can change – and an indication of the relentless nature required to succeed at Celtic Park.

“Exactly, that’s life at Celtic,” McGregor agreed. “You don’t win for a few games and there is a crisis!

“It’s a good lesson for the new players. It doesn’t matter how well you think you are doing, a few results and you are right back to earth.

“Hopefully the guys will take that learning and it’s the same for the rest of us. You can never really come off it at Celtic but we have a game on Saturday and then it’s all about the cup final.”

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As for that showpiece occasion at the national stadium, McGregor is convinced that when the players cross that white line and stride onto the Hampden turf, they will raise their game and will have ironed out the creases of the last few weeks.

“Yeah, we can,” he added. “The last few games haven’t been great but I have no doubt. I am full of belief.

“We have big game on Saturday and it’s a chance to celebrate the title, and for the supporters to celebrate and unbelievable season in the league. We already have a cup in the bag and after Saturday, full focus switches to the final.

“I have no doubt that we will be ready to go for Hampden. We have a good track record of coming through the big games and the big moments.

“We have been strong as a group. That gives us the confidence that we will be ready to go for the final.”