European royalty, every one of them, as their impressive record of lifting Europe's top prize underlines.
But Neil Lennon has now had time to take stock, and reminded himself he has helped reintroduce Celtic to Europe's elite with a run to the last 16 of last season's Champions League.
"We should not feel in awe any more, we should feel part of it," is the manager's take on what most perceive to be jousting with giants.
Last term's achievement was crafted against a backdrop of dismissive negativity, very similar to the reaction when Celtic's name came out in yesterday's draw.
He acknowledges it will be even tougher this time around.
Barca are still Barca, but Benfica have been replaced by AC Milan and Spartak Moscow by Ajax, arguably two more formidable opponents than the Portuguese and the Russians.
At the same time, with Victor Wanyama, Gary Hooper and Kelvin Wilson among the seven players Celtic have lost since they went out to Juventus in March, his own side does not look as strong.
Which is why the next couple of days before the transfer window closes in Scotland could be pivotal in terms of how competitive Celtic can be in Group H.
With another £15million guaranteed for reaching the group stage, added to the £2m- plus gate money earned from the qualification and play-off matches to get here, there is money to spend.
The manager wants to be given the opportunity to do so.
Israeli midfielder, Nir Biton, is already on board, having obtained his work permit, and hopes are high that Finnish striker, Teemu Pukki, will not be far behind.
Cover for Emilio Izaguirre at left-back would be appreciated by the manager, but a multi-scoring penalty-box predator is what he craves most.
To give Celtic a chance of upsetting the odds - which, for qualification, jumped from 4-1 before the draw to 10-1 immediately after it - they need to strengthen in this key area.
The first group game is under three weeks away, little time to sign and settle a new striker.
But the lure of games against Barcelona, Ajax and AC Milan might make it that bit easier to convince one to join the Hoops bandwagon.
Lennon hopes so. He can't guarantee any potential signing success in the Champions League, but he can promise them a fabulous experience.
And it's the experience garnered last season which will be the foundation on which he plans to mount his campaign this time around.
When Benfica came to Glasgow last September for the first group game, 10 of the 11 players Celtic fielded were tasting Champions League football for the first time.
It could be the other way around this time, and that's going to be a huge help.
By the time the first whistle blows, Lennon will have done all in his power to convince his Bhoys they are a match for the men facing them.
For now, however, he is just happy to be looking forward to having the opportunity to test his team and himself again at this level.
"In terms of difficulty, I don't think you could have asked for anything more, in terms of the quality of teams we are going to face," said Lennon.
"But the hard work was done on Wednesday night and over the last six or seven weeks. Now we can enjoy it.
"The players can savour it, and so can the supporters.
"We are going to be playing three wonderful football clubs."
He accepts expectation has risen in tandem with their co-efficient, but is entitled to point out that this is still so low it keeps them in the bottom pot when draws like this are made.
That means they are scheduled to finish fourth in the group and exit Europe before Christmas, Lennon joking that they are the runt of the litter, such is the pedigree of the others in Group H.
However, as last season proved, Lennon and his players are not just happy to wag their tail and roll over; they want to get their teeth into this competition.
Barcelona will need no reminding they can bite, while AC Milan and Ajax will also have taken note of how they over-performed last season.
Lennon really wanted to be pitted against Real Madrid, so up for the challenge is he, and said: "You just never know with this bunch of players what they are going to bring. We could get no points, we could 10.
"The pressure is off in terms of I don't think anyone really has huge expectations on us to qualify, although some of our fans who set very high standards will be expecting that.
"The experience of last year will stand the players in good stead. They played against Barcelona and qualified for the last 16, and played Juventus.
"So don't think that they will be fazed with it."
Maybe not, but it will take more than bottle and nerve to make their mark in this group, and that's where adding extra quality to the experience they have will be crucial.
When the squad is registered on Monday night, it has to have an injection of fresh blood, blue blood if Celtic are to be anywhere near capable of living with European royalty.