LAST SEASON, Callum McGregor lifted three trophies as Celtic captain. Over the past week or so, he’s been copping some flak for his recent performances as the champions have exited the League Cup and drawn at home to a struggling St Johnstone side.

Such is life as a Celtic player. Even the most popular, longest-serving members of the squad are not immune from criticism when there is a wobble on the park. Transitional period or not, the unforgiving glare is almost written into the contract.

As a former Celtic midfielder himself, Paul Lambert knows this all too well. But he also knows that there is no way McGregor would have enjoyed such longevity at Celtic if he wasn’t able to handle it, and if he didn’t understand what is required to come through times of such scrutiny.

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So, while Lambert is unsurprised that even McGregor has come in for some stick of late, he is equally as sure that he will soon be back to his best.

“Can I believe he’s being criticised? Yeah, I can believe it, because this is Celtic and you are only as good as your last game,” Lambert said.

“Callum will know that himself, you are there to be shot at, but he’s big enough to come through it.

“He’s been brilliant for Celtic, but as soon as you get a couple of bad results then people will start asking ‘what is the matter with him?’ or saying ‘that pass wasn’t good enough.’

“That’s normal when you’re a Celtic player, but if you are big enough to carry the weight of the shirt then you’ll be totally fine with that, it will be easy for you.

“I don’t think that will bother him to be fair. He’s been there long enough to take the criticism, and knows that comes with the ticket when you sign. And so it should, with the size of the club.

“You are there to be shot at and you have to be able to handle that side of it. He has handled it brilliantly throughout his career, so after one or two bad games, I wouldn’t think it would bother him. He’ll take it on the chin and just play his normal game.

“As the team starts to pick up, he will start to pick up. I don’t think that will be an issue for him.”

There would be no better time for McGregor to roar back to form than this Sunday as Celtic face Rangers for the first time this season.

They travel to Ibrox as a team out of form as they transition from Ange Postecoglou’s style to the preferred approach of Brendan Rodgers, carrying injuries to key personnel, and will likely – if all goes to plan in the final days of the transfer window – be throwing brand new signings in at the deep end.

If they are going to emerge from that test without suffering another morale-sapping result, Lambert believes that McGregor’s leadership will be vital.

“He’ll be as big as he has always been for the club over the past 10 years or more,” he said.

“He is going to have to perform, like the rest of the lads, in a difficult place with none of their own fans there. They are going to have to play through that.

“I don’t have any worries about Celtic going there to handle that game mentally, because they have been there and done it before and the manager has been there and done it before, so I don’t see any major issue with guys not being able to handle it.

“It’s an Old Firm game, which is what it is. It’s mad for 90 minutes. But if you can keep your head and keep cool under pressure, then they can have a good game I think.

“Every game with Celtic was big anyway when I played, but especially with the Rangers team we played against you knew you had to be up for it, because they were a right good side.

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“The two of us were good teams, to be honest with you, and we were big enough mentally to handle the importance of those games.

“We didn’t need anyone to gee us up or motivate us, we knew the magnitude of the game that was before us, and we were all big players who had played in big games before.

“Callum is the same.”

As well as the reassurance that McGregor’s experience brings for Celtic fans ahead of the clash with Rangers, Lambert believes there is succour to be found when it comes to the crucial last knockings of the transfer window in the experience of the club’s manager.

Rodgers has publicly admitted that his squad requires quality over the next few days if they are to achieve their goals for the season, but Lambert says he will have the situation under control.

“I think Brendan will know exactly what he needs and what he requires,” he said.

“He’s a top manager and Celtic know what they have with him. He’s done it before, and he’ll know exactly what his team needs.

“The structure will be strong at Celtic because of the success they have had in recent years and because of the Champions League money and transfer revenue.

“They have a top manager there who will know exactly what he needs and what he doesn’t need, so I don’t worry about Celtic.

“Brendan will get his teeth into it, I have no doubt about that. He’ll know it’s a challenge because of what has happened in the last couple of years, as everyone now thinks that if you haven’t won the treble then you’ve failed, which is incredible.

“If Celtic can get a result at the weekend and they get a favourable draw in the Champions League then suddenly things can change and that would be a good start for them.”