As the final seconds of the contest ticked down, Brendan Rodgers took a brief moment to observe the chaotic scene unfolding around him.
Young Boys were looking for an equalizer at the last moment, but Kasper Schmeichel got the ball right. Ninety-five minutes had been played. The game was over.
Celtic Park was in a state of ecstasy. The 12-year wait to reach the last 16 of the Champions League was over.
This coveted victory allowed Celtic to achieve their stated goal with one game to spare.
He also offered vindication for the coach and his superiors who ignored the noise and brought him back to the club in 2023.
After three failed attempts to crack the code in two spells, Rodgers has returned the club to where he feels it belongs.
Adam Idah watches as his shot deflects off Young Boys captain Loris Benito for the only goal.
Idah wins praise after Benito's OG secures Celtic's place in the last 16
Celtic manager Brendan Rodgers greets the Parkhead supporters at the end of the match
Celtic, who have participated in this competition for so long, are competing in it again.
The success has come from showing more mettle away from home, but mainly from restoring Celtic Park's reputation as a place where rival teams fear to tread.
Having picked up just five points from a possible 18 at home in the last two campaigns, this time Celtic have taken 10 from 12. Their fortress walls have been weighed down.
A trip to Villa Park next week will be made without any sense of danger. Rodgers' side will need a win and some good luck elsewhere to sneak into the top eight and go straight to the last 16. It's unlikely, but still possible.
They have certainly earned that free hit. The gloomy night in Dortmund aside, they have been hugely impressive along the way. Able to defeat RB Leipzig at home and knock out Atalanta, the team has evolved and matured.
The Swiss faced stubborn opponents and were only defeated by an own goal from their captain Loris Benito.
Celtic did not dominate as they expected, but they showed resilience when necessary. They stayed there knowing that a point wouldn't have been a disaster, but they came strong at the end to overcome it. As for the opportunities they created, they deserved it and all this will bring now.
The great start they expected did not materialize. This had as much to do with the yellow defensive barrier that the Young Boys put up as it did with Celtic's lack of cunning.
Hopes that Kyogo Furuhashi had made the initial breakthrough were dashed by an offside flag.
Nicolas Kuhn's first intervention was typical: he rushed down the right wing and shot. The slightest deviation caused him to go astray.
Daizen Maeda's interception allowed Reo Hatate to free Furuhashi. A weak shot didn't faze Marvin Keller.
Arne Engels took a while to get going. Once he did, the Belgian released Kuhn. Only a brilliantly timed clearance by Mohamed Ali Camara prevented Furuhashi from scoring from three metres.
The Swiss were happy to camp in their own half, they still had their moments, none more so than when Joel Monteiro forced Kasper Schmeichel to save his deflected shot from 30 yards.
Hopes of a penalty when Cheikh Niasse clumsily caught Maeda came to nothing.
Hatate moved his feet on the edge of the area and shot wide. The goalkeeper saw it late and diverted it for a corner.
Callum McGregor's challenge on Niasse saw him seemingly win the ball high up the park. Furuhashi swung, weaved and caressed the ball. The VAR intervention caused referee Rohit Saggi to approach the monitor to consider the captain's intervention illegal.
Maeda was getting enough encouragement from the left. Another cross pointed at Furuhashi. For the third time in the first half, the forward scored. The linesman's flag ensured he still had to score.
It was obvious that the Swiss were beginning to feel the rhythm. As Greg Taylor reached Darian Males' goal, a lazy hand on the shoulder saw the winger fall to the turf. Grief.
Normally so reliable from 12 yards, Engels broke his run. The goalkeeper didn't take the bait, he waited for the ball to be hit before moving. He made a simple stop to his left.
Celtic finished the half with a flurry. Engels' corner was sweetly collected by Furuhashi, but an outstretched leg ensured the ball went wide. Hatate parried a fizzing shot and then volleyed just wide.
Arne Engels has his penalty saved as Celtic failed to advance in the first half
Rodgers' men had created enough chances but the final product was again lacking.
The theme continued after the change. The Angels' shot was missed by the goalkeeper. Maeda sent the rebound over the crossbar with his head.
Maeda made a clever one-two punch with Engels. Keller blocked the winger's angled shot before repelling a blow from McGregor.
Another Engels corner was claimed by Auston Trusty. This time the bar saved the Swiss.
Celtic pressed, but there were moments of anxiety. Schmeichel made a spectacular double save to prevent Darian Males from giving the visitors the lead.
The introduction of former Rangers striker Cedric Itten only increased the tension.
Paulo Bernardo was asked to introduce some dynamism but was careless with the ball. The Portuguese were not the only ones in this.
Just when it looked like the match would end in frustration, a quality boost turned it in Celtic's favor. Hatate dropped a shoulder on the left flank, left his man for dead and sent a peach ball behind the defence.
Fresh off the bench, Adam Idah charged towards the goal. His shot was stopped but bounced off Benito and inched over the line. Cue chaos.
The final moments would have been quite hectic. A red card to Maeda at the behest of VAR after being shown an initial yellow card for a kick on Camara made it even worse.
But they got there. And they are there. The almost men of the Champions League no longer.