The brutal truth of Celtic's misery years in Europe is that the player who has been the totem of this team for so long is also the one who has suffered the most when things have gone wrong on the testing grounds of Spain, France, Germany and beyond.

Callum McGregor, 31, is a modern great of the club, but he bears the scars of Celtic's failings in unforgiving places like few others. It's him and James Forrest. They have run the full gamut, from Brendan Rodgers to Neil Lennon to Ange Postecoglou to Rodgers 2.0.

Rodgers has won 23% of his European group and knockout games as Celtic manager, losing 63%. Postecoglou won 21%, Lennon, in his second spell, won 36%. McGregor was there for the vast majority of them - 58 games, 15 victories, 26% success rate across eight-and-a-bit seasons.

It's a lamentable return and if the bookmakers are to be believed then it's going to continue, with bells on. They all think Atalanta will beat Celtic comfortably in round three of the Champions League on Wednesday.

In the betting for first scorer, the first nine options are Atalanta players, then it's Adam Idah, then a bunch of other home players.

McGregor's the on-field leader, the one who must try to shed the memory of so many bruising nights while at the same time exuding total belief. That's a hard trick to pull off. There is serious Celtic trepidation going into this one.

He played in last season's 6-0 loss to Atletico Madrid, the 7-0 in Barcelona, the 7-1 at Paris St-Germain and the 7-1 to Borussia Dortmund last time out.

He was in the team when Copenhagen dumped them out of the Europa League, when Bodo-Glimt put them out of the Conference League and when Sparta Prague put eight goals on them in two legs in the dog days of 2020-21.

So much silverware at home and so much suffering away from home. McGregor, though, is a warrior and he goes again. Celtic need more guys in his image.

Nobody gives them a prayer, which is fair enough. Atalanta are sharp, pacy and full of goals. They have recovered from an early season dip to take recent opposition to the cleaners.

Atalanta must have looked at all the space Celtic afforded Dortmund and licked their lips. In the wake of that pummelling they must have listened to Rodgers' steadfast belief that his way is the right way and that it would not change for the trip to Bergamo and smiled.

McGregor deserves better than another humiliation, which must be the fear of all Celtic fans. Lemmings at the cliff edge have shown more aversion to danger than some of Celtic's performances in Europe in recent times.

It's almost unthinkable that Rodgers will set his team out in Bergamo the way he set it out in Dortmund, but he's been unyielding in his view, despite much evidence, that this is the way results will improve against the better sides in Europe.

Rodgers is brave, in a sense. He's sticking to his guns, no matter the noise. He's totally sold on the belief that things will turn around soon enough.

What he sees, few others see, but if he's to be proven right then he needs some encouragement on nights like this. He needs some ammunition to fire at all the sceptics. A combative performance is required.

That type of display becomes all the harder when you note Celtic's penchant for imploding under pressure, their ruinous habit of conceding goals in bunches.

They conceded the first two in Dortmund in four minutes and conceded two later on in three minutes. It was the continuation of a brutal trend.

They conceded in the 82nd and 85th minute against Lazio in Rome last season.

They conceded in the 60th and 66th minute against Atletico in Madrid.

Postecoglou's team had this weakness, too. Real Betis. Real Madrid and Leipzig all scored twice in rapid order in games on his watch.

It was also a feature of Rodgers' first spell. Barcelona scored three times in 10 minutes. PSG scored in the 34th and 40th minute and in the 83rd and 85th minute in one game and in the 22nd and 28th minute and in the 75th and 79th minute in the other.

Salzburg scored twice in six minutes in a Europa League game under Rodgers. Leipzig, again, scored two in four. What chance have you got when that happens?

Celtic do not need to get anything from this game in terms of points - easier matches lie in wait later on - but the restoration of pride after the debacle in Dortmund is a must. For the team and for Rodgers himself.

Rodgers has been a brilliant domestic manager, but in European terms he has been decidedly second-rate at Celtic, the owner of some of the most excruciating losses in the club's history.

The last marquee European victories were the home and away triumphs against Lazio in 2019. Lennon was in charge.

Celtic need more performances of that ilk and resilience under pressure is part of it. Too often in this type of game they have made it easy for opponents to play against them in critical moments rather than being the nightmare rival that Rodgers wants them to be.

McGregor will be at the heart of it for Celtic. For his sake, onlookers would want him to be the spearhead of a resounding display rather than being the one chasing shadows again. Rodgers says he's excited. That's one word for it. There are others.