It shouldn't be a problem at the next one. Just four days after a quarter-full stadium witnessed second division Arbroath secure an unlikely William Hill Scottish Cup replay, Celtic Park will come alive once more tomorrow night. The Champions League has had that effect on them this season.
As fourth seeds, Celtic were given little chance of making it out of the group. Now they stand on the cusp of joining Barcelona in the last 16. It is not in their own hands – a Benfica win at Camp Nou will be enough to secure second place for the Portuguese – but they have made it to the final group game with qualification still on the cards. Victory over a Spartak Moscow side with nothing but pride and an interim coach to play for would leave them with 10 points. Teams have exited the competition on that total before – Manchester City last year, for example – but it would seem a massive stroke of bad luck for Neil Lennon and his players if a campaign that has already delivered so much were to end on such a deflating note. Barcelona, they must hope, are willing to play their part.
Celtic have already secured European football after Christmas but the Europa League will seem like a somewhat unappealing second prize, the slush after the snow, after everything they have been through in the Champions League. Beating Spartak in Moscow was a landmark – a first away win in the group phase – but that has almost been forgotten by the acclaim that has poured down following the defeat of Barcelona. It has lead Celtic to this point, a dramatic denouement at home that could have sold out five times over.
Even former players who have experienced frenzied European nights at Parkhead many times in the past are cursing their luck that they won't be back for this one. "It's a big night and it's going to be fantastic," said Pat Bonner, the former Celtic goalkeeper. "Most people will want a ticket for it but they're not to be had.
"I don't think [many people expected Celtic to go through] because they hadn't won away from home and that's what they wanted to improve on. So they probably didn't expect to be going into the last night with a fantastic opportunity. It's been almost a year-and-a-half of work to get to this point so if you're a Celtic player, fan, staff member or on the board, these are the type of nights you want to be around the club and making history. They haven't been that creative this year, they have struggled a little bit on occasions to score goals but I think Wednesday night takes care of itself. They'll be up for it and I fully expect them to win the game."
As someone who spent two decades on the books of the club, it is hardly surprising that Bonner tends to view things through a Celtic prism. But he believes if Lennon's side can take their place in the last 16 it would benefit the whole of Scottish football. "I think it would be a huge achievement if they could do it," he said. "I think the club is probably a stage ahead of where it expected to be after a couple of years of development.
"To get there would be great – and it would be great for Scottish football as well. I think we need a team at that level. This year Celtic are promoting what Scottish football is all about. I travel a lot and listen to people talk. Last year they spoke a lot about the Rangers scenario because it was headline news. This year they are talking about Celtic. And that will only increase if they qualify. That kind of positive light is what we want."
An intriguing subplot revolves around Aiden McGeady. The former Celtic player returns to the east end of Glasgow for the first time since leaving for Moscow two years ago intent on depriving his former club a place in the last 16. Bonner knows McGeady well – it was he who helped smooth the player's path into the Republic of Ireland set-up – and thinks the 26 year-old will be keen to impress.
"He will want to come back and put on a bit of a show," Bonner said. "I know he has had problems with his fitness, but I think he will play. They have a new manager in Valery Karpin, who was previously sitting upstairs but is now back on the touchline. I think the players will be wanting to impress him. He will be questioning whether a few of them should be at the club because of their results in Europe this season, so they will be looking to redress that.
"It is going to be a night of nerves and Aiden will play his part in that. There's no question he will be wanting to impress, even though there is no question he is a Celtic supporter deep down. He is a professional and will want to do well for his club."
While McGeady will likely be heavily involved from the start, one of his successors in the Celtic team will need to settle for watching from the stand, a hamstring injury denying James Forrest the chance of lining up against the player he considers to be a role model.
"Aiden is a top player," said the Celtic winger. "We regard him as Spartak's best player and their biggest threat so we'll need to close him down. He'll want to show our fans that he's still got it. He wasn't too happy with how he performed against us in Moscow [in the earlier group game] but this will be his first time back at Celtic Park so he'll have a point to prove.
"Aiden plays in the same position as me so I used to watch him every day and learn from him. But Wednesday is massive for the club, probably the biggest game we've had in the last five seasons. Everybody believes we can get through."