The victory in Paris for the side of Jürgen Klop will almost certainly put them in the last 16 – but what's the worst case scenario?
For Liverpool, big games continue to come.
Jürgen Klopp called this "most intense period of year-round", and it's hard to argue with the head of the reds. Defined period? That could be.
Merseysit's action, once, can wait. The Premier League clash on Sunday is huge, but so far it's bad compared to the challenge facing the Reds on the continent.
Clopp and his players seemed relaxed as they arrived in Paris on Tuesday, but there will be no room for complacency. Paris Saint-Germain, a club built for success in the Champions League, awaits them.
The scene is set, the stakes are high and Neymar is expected to be appropriate; Kianan Mupe also. Edinson Cavani will be there. Thiago Silva. Gigi Buffon. Big names, big tests, big night, in more ways than one.
Victory and Liverpool will almost certainly be in the last 16. Draw and they will be in the box.
But lose, and unimaginably comes into consideration. Can the finalists pass the season, the team that thrills the world on their way to Kiev, will hit the first hurdle this time?
It really should not have come to this, but at the last moment in Naples and a shocker from the play in Belgrade they left Klop to the side. It is likely that they will have to beat Napoli at Anfield in two weeks, perhaps with two goals, for progress.
Not the worst scenario in the world – The Red Powers in the past faced such challenges, I remember – but still take care.
As you feel the good factor around Anfield grows every minute of a week – Watford's victory continued its unusual start of the Premier League season in 13 games – the Champions League exit would be a big blow.
Financial, the impact would be obvious. Liverpool earned just under 70 million pounds ($ 89 million) from running until the last season and will, of course, focus on a similar exciting prosperous campaign this time.
Their participation in the group phase will guarantee them $ 13.5 million ($ 17.3 million), with additional payments of £ 2.4 million for a single victory and £ 800,000 ($ 1 million) per draw, in addition to their share of substantial TV – the right pool and the new UEFA coefficient ranking, which pays clubs according to their performance in the European competition for a period of 10 years.
Now you go out, and the Reds miss out with a guaranteed £ 8.4 million ($ 10.8 million) for a match in the last 16 years, with a gradual payout that is available after progression after that. For example, in the final, for example, an additional £ 33.1 million ($ 42.5 million) will be added to the prize.
More important, however, would be the sporting consequences. Liverpool is up, but failure here will check their progress. In many ways it would be a bigger blow even from their defeat to Real Madrid in May.
This, I remember, is a composition that has been strengthened in order to deal with the demands of the competitions on several fronts. And while their home campaign goes well, the idea of Liverpool falls into the Europa League after Christmas appeals to no one. Except maybe Manchester City.
Night trips to Krasnodar or St. Petersburg on Thursday will do nothing to help red titles, and the sale of the club for potential transfer purposes is undoubtedly easier if you illuminate their television screens on the big scene every week.
Like Virgil van Dyck, Nabi Kiita, Fabio and Mo Salla bought the vision that Klop showed them, but that vision ultimately requires top success at the top. Without him, because Liverpool has been for more than six years, there is a danger of penetration. You're fine, but you're not.
Last season was, in many ways, more than football for Liverpool. It marked the return of the famous red spot, a reminder that the five-time European champions can still be the force in this modern era of petrodollars and superclubs. It brought hope and excitement that, perhaps only, the future could be as glorious as the past in the brightest English football club.
The defeat in Paris, or indeed against Napoli, will not extinguish that hope, but it will surely bring questions. Liverpool's team was tough, but they would still think their chances of progression. Even more, after defeating PSG in the first game.
That night was a continuation of last season's form, an exciting atmosphere and a performance that was supposed to match. Enfield can specifically be said. That night, I felt that nothing had changed. The machine was to roll.
Far from home, however, it was another story, shows in Naples and Belgrade were a significant step backwards, and putting reds in this precarious situation.
Clopp's team lacked confidence and conviction, weakly crossed the ball and looked lethargic, especially in the middle row.
Clopp took the risk of bursting with his team in Belgrade, leaving key players and trusting those without a sharp line on the sword. Do it too often and you will be punished. Liverpool have now lost the last four European matches away from Anfield.
The return to be formed on Wednesday will be welcomed. PSG is a team of stars, but their record from the Champions League shows they are still far from the elite team.
League 1 is their comfort zone – they have won all 14 games so far this season – but from that they can struggle to increase their levels. A victory in four group games says that, as it comes out of the hands of Real Madrid, Manchester City and, most famous, Barcelona in recent seasons.
Klop has the measure of Thomas Tuschel, opposite his opponent number, at recent meetings, noting his side of Borussia Dortmund in the Europa League in 2016 and the astonishing PSG in late September.
Tuquel has more reasons than most to get sick from the eyes of men in red, and knows that the exit from the group stage will bring questions about his future at the Parc des Princes.
Clopp's position, of course, is far safer. There should be no knee response, if Liverpool crashes, and should not exist. The club, obviously, is heading in the right direction under the German one.
The trick is now to ensure that their journey is not delayed. One victory should do it. How Red would like it to be received in Paris.