Paris Saint-Germain forward Randal Kolo Muani maybe went a little too far. "The game against Dortmund? Our lives are at stake," he said after Saturday's 2-1 win against Nantes. He certainly didn't mean it literally, but the basic idea is clear: Borussia Dortmund vs. PSG is huge for the Parisians.

Their final Champions League Group F fixture on Wednesday is the game that will define their season, which is saying something considering it's the second week of December.

- Stream on ESPN+: LaLiga, Bundesliga, more (U.S.)

PSG's German opponents have already booked their place in the round of 16 but are not guaranteed to top the group. Meanwhile, PSG need a win to make sure they are through; if they do win away from home, they would finish first instead. A draw could be enough to advance to the knockout phase next February, but only if AC Milan win or draw in Newcastle United; defeat in Germany could still see PSG go through, but only if Newcastle vs. Milan ends in a draw. Another combination of results would see PSG suffer an ignominious drop into the Europa League.

"It is like a final," added Kolo Muani, who has just celebrated his 25th birthday with a party in the French capital. There could be no better belated present for him and his teammates than a place in the next round. Despite the clear importance of Wednesday's game and the pressure that comes with it, the camp is pretty calm and composed. On Saturday, the players clearly had their minds on Dortmund instead of focusing on Nantes, their opponents at the Parc des Princes. It was an inspiring performance and victory -- Muani scored the winner seven minutes from time in a game PSG had largely dominated -- and they probably celebrated his birthday more than they did the win over the Canaries.

The only thing of note, perhaps, is Luis Campos' consistent presence around the squad. The PSG sporting director did an interview before the Nantes game to remind everyone that his team "is not scared, and that it is an exciting game to play." He was in the tunnel at half-time to congratulate the players for leading at the break, and he was there again after the victory. He is always hands-on when it comes to his role, but has been even more visible around the team these past few days.

Wednesday's game is massive for Campos as well, because it would be his failure to share if this team didn't make it to the round of 16. PSG have done it every year since 2011-12, and missing out would make him the first sporting director of the club's Qatar era to oversee such a embarrassment. He would not be able to explain his way out of it, either; he built this team in the summer, adding the likes of Kolo Muani, Manuel Ugarte, Ousmane Dembélé and Bradley Barcola at great expense. If they aren't good enough to qualify, he would be to blame.

Luis Enrique would also bear responsibility should the worst-case scenario come to pass. In a group that did not appear to be that tough for PSG when the draw was made -- given the uneven domestic form of Newcastle, Dortmund and Milan this season -- it would be seen as a disgrace if coach Luis Enrique didn't get his team over this hurdle. There have been a lot of positives since he joined the club this past summer, and his team plays with a clear identity, but his tactics have been baffling at times. Take the 4-2-4 formation that failed at Newcastle, or keeping Goncalo Ramos on the bench until the 85th minute at home against the Magpies in the return fixture.

Despite the pressure, the Spaniard is keeping cool; he's not showing any signs of nervousness or tension to his players or his staff. The 53-year-old is experienced at the top level and is always confident in both his abilities and his team, regardless of the opposition. On Sunday morning, he was relaxed at the training session, laughing and joking with the players, switching to full preparation mode on Monday.

On Sunday, Luis Enrique spoke to Lee Kang-In, who should replace Dembélé on the right wing against Dortmund. Dembélé's suspension is a massive blow, as a lot of PSG's build-up depends upon his partnership with Achraf Hakimi. A lot of the passing circuits go through him, making him their main creator. We saw it against Nantes, as PSG woke up when he came on with 25 minutes to go. Before that, the pace and rhythm of every PSG attack was a lot slower. Lee is a different type of player than the France international he's replacing. He doesn't have the same pace, but he can be a difference-maker with his dribbling precision and technical ability.

Another reason Luis Enrique might be quite relaxed at the moment is because he knows he can count on Marquinhos and Warren Zaïre-Emery in midweek, as both successfully returned from injury on Saturday. The Brazilian defender played 60 good minutes, while the Paris-born prodigy came on for the last half-hour and looked as though he'd never been out of the team. Both of them will start in Germany, and PSG will be a better team for it.

Like Luis Enrique said to his players, it is time for PSG to be a real team and take control of their destiny. It is all in Paris' hands, and they simply can't afford to buckle under the pressure on Wednesday like they have done in European campaigns of the past. Just as Kolo Muani claimed, their lives in the Champions League are at stake.