Or can Neil Lennon's side ensure Zadok The Priest is put on repeat for the next four months by overcoming Shakhter Karagandy and securing their place in tomorrow's group stage draw?
It is an accurate indication of what is on the line, and an instant barometer of the pressure building, that Lennon and his Shakhter counterpart, Viktor Kumykov, have engaged in psychological warfare ahead of tonight's play-off second leg.
Both bosses are feeling the heat, for very different reasons.
Lennon does not want to suffer a bloody nose or to have last season's achievement in progressing to the last 16 dismissed as a fluke, which will be a temptation for many if his side fail to even reach the group stage this time around.
The Hoops were huge favourites going into the play-off ties against Shakhter, the bottom-rated club in this round.
If the Kazakhstan champions - now the bookies' tip to go through - can add their scalp to that of BATE Borisov and Skenderbeu, they would become national heroes as the first club from that country ever to reach the final 32 of the competition.
However, that opportunity in itself has cranked up the pressure on Kumykov.
And the fact Shakhter have arrived in Scotland with a two-goal advantage from the first leg means expectation level back in Kazakhstan has risen disproportionately to their standing in the game.
So it is not surprising the words emanating from both camps have been provocative, to say the least.
Kumykov appears to have taken umbrage at Lennon's comments before the first leg in Astana when he said he would like his team to score twice to make the return more comfortable.
This was translated as a boast that the Hoops boss believed his side would win by that margin.
Now it is the newly-emboldened Shakhter's turn to have their say, and Kumykov has upset Lennon by suggesting they could score two tonight to add to the pair they notched in the first leg and take the tie and the group stage beyond Celtic.
Who needs to slaughter any sheep when the respective managers are going for one another's throat?
However, it is who has the final say that matters, and Lennon is determined it will be him. He conceded: "There's a lot riding on the game. It's so early in the season and we've always maintained these games are the hardest for us to overcome for varying reasons.
"But I think the players are still angry from last week. There's always a fall-out after these games and things get said, so they will be very motivated to prevail."
For this to happen, his players have to rediscover the defensive solidity which saw them go seven qualifying and play-off games over two seasons without conceding before they capitulated so cheaply in Kazakhstan.
They must also find their shooting boots again, along with their composure throughout the team, but especially in front of goal.
Chances to score will be created this evening. Shakhter's porous defence and shaky goalkeeper were fortunate to survive in the first leg, and lost three goals within the first half an hour of their qualifying tie in Albania in the previous round.
That brought the tie with Skenderbeu level, but they did steady the ship and scored twice to book their place in the play-off.
The notion Shakhter had used up all of their luck as they disposed of BATE Borisov - a group stage competitor last season and the only side to record a victory over eventual Champions League winners, Bayern Munich - was dispelled that night in Albania.
Celtic must hope it is their turn to get a nod from Lady Luck, after she turned her back on them in Astana.
But the old saying you make your own luck will be at the front of their minds, and the Hoops know they must impose themselves on the game, take the chances when they come along and keep the door closed to any threat of an away goal.
There is no doubt an early goal would help, as it would settle Celtic and their fans and should have the opposite effect on Shakhter.
However, Lennon is focusing only on how his players perform as he admits he does not know how Shakhter will react to this new experience.
"Sometimes dealing with it for the first time, there is no fear or you have no worry about the consequences," he reasoned. "There's no real pressure on them, and there hasn't been since this draw was made.
"However, it's different when you are on the pitch and you are away from home if the opposition get a head of steam up. That's when you start to feel the pressure.
"We might not score until the 70th or 75th minute, but that still gives us 15 minutes to get another one. That's a long time in football."
Lennon's repeated prediction that, if Shakhter score one, Celtic will score four, is concerning as it indicates the manager is not entirely confident his defence can keep out the Kazakhs, who he rates as a top four or five-level SPFL side.
On a good day, they may be on a par with, say St Johnstone or Dundee United. But, unlike those two clubs, they will never have experienced anything like the wall of noise which awaits them at Parkhead tonight.
They will attempt to erect their own wall - and it will take guile to unlock the deep-sitting Shakhter defence - predatory instincts to pounce and convert the chances created, concentration to foil any attempted breakaways, and nerve to keep all of the aforementioned going if the goals do not come early.
It is the antithesis of playing Barcelona on that glory night last season when Celtic could sit in, soak up the pressure from Messi and Co. and pounce at a set-piece then on the break to record one of the most famous results in the club's recent history.
Above all, they have to make their superior quality count, because the consequences of failing to do so will extend well beyond the disappointment of dropping down to the Europa League.
It iS not hyperbole to say the outcome of this tie will define Celtic's season, and perhaps longer, in terms of players looking to be offered new contracts and others hoping to join the club.
Whether it is 90 minutes, 120 or after a penalty shoot-out, the Champions League theme has to still be playing.