[BBC]
Tonight in Austria is about one thing. Getting the job done.
After that brilliant first-leg performance, Celtic take a three-goal advantage into the return knowing if they see it through we're back in the Champions League proper.
On the face of it, that is the prize.
But qualification should change much more than simply putting Celtic's name back in the draw...
The financial question
The most obvious factor is money. Champions League qualification brings a completely different level of revenue and while Celtic are hardly scraping around financially, that extra income is still vital.
Especially with only a few days remaining in the transfer window. Because if Celtic qualify, the conversation immediately changes from "Are we good enough to reach the Champions League?" to "Are we good enough to compete once we get there?"
Recruitment this summer has been encouraging. Camilo Duran has made an instant impact. Kasper Hogh gives something different through the middle, while Mika Baur and Haissem Hassan have added further quality and options.
But qualification should sharpen the focus even more. Suddenly, Celtic know exactly what level they're preparing for.
And perhaps that provides the extra push required to add another two or three key players.
Status still matters
Then there's the prestige. Despite the changing landscape of modern football and financial dominance of Europe's biggest leagues, Celtic should be a Champions League club.
It is where the club, players and supporters want to be. And after last season's painful exit against Kairat Almaty, getting back there makes a statement.
It would make last year look like a setback rather than the beginning of a wider decline.
Champions League football matters to players too. Top players want that big stage, those nights and that level of competition.
It helps with recruitment. It helps with retention. And it makes Celtic a far more attractive destination.
The ultimate test
There's also the sporting challenge - this Celtic team needs tested properly.
Domestic football can only tell you so much, but the unforgiving Champions League environment exposes everything.
Quality, concentration, decision-making, defensive weaknesses and squad depth.
As impressive as Celtic's start has been, we don't yet know the ceiling of this team. Europe's toughest competition would provide the answers quickly.
Qualification should be the beginning
That is why tonight is about much more than just another qualifier.
It could influence Celtic's transfer business, their ambitions, the mood around the club and the expectations of the entire support.
First things first of course. There are still 90 minutes to negotiate in Austria.
But if Celtic finish the job, the next question becomes every bit as important: Do they simply celebrate Champions League qualification and consider the summer a success?
Or do they use it as a platform to push again, strengthen again and build a squad genuinely capable of making an impact?
And that's where things could start to get very interesting.
Tino can be found at The Celtic Exchange