Celtic come into the contest with just 3 points so far and have to take on a PSG side that has 12 points after winning all 4 of their previous games, scoring 17 times and conceding 0.
If Celtic could conjure up a victory against the high-flying Parisians, it would be almost as colossal as their victories over Barcelona and AC Milan in years gone by. But just how could they upset the odds and beat PSG?
Here are three tactical tweaks that could help them do the job:
1. Sit deep and be compact
PSG's front three are all absurdly quick. Neymar and Kylian Mbappé are both capable of breaking the sound barrier when they get going. To counter that, Celtic have to sit deep and be compact. They should not only allow little space behind them, but also make sure there's no gaps between their midfield and defence where PSG could build attacks.
2. Play two-man attacks with a third-man running
Brendan Rodgers is an adventurous coach. His teams always set up to be proactive and exciting. That's great, but against PSG it would open him up to getting ripped apart on the break. So to build off the idea of sitting deep and being compact; when Celtic are going to attack they should only do so with two men.
Let Moussa Dembélé and Leigh Griffiths run a two-man attack, working with each other to find space on the break and hurt PSG, and then let them be joined by late runs from Scott Sinclair. Attacking with so few men would mean PSG would pile more men forward and, as long as the Celtic defence holds, there could be ample chances on the break.
3. Be aggressive from the start
This is not say Celtic should go around kicking lumps out of the PSG players, but they absolutely must be physical from the first minute. The key to getting away with an overly-aggressive style of play is to be consistent with it. Referees won't punish you for every foul you do, so if you do them all the time you'll get away with more.
In this aspect, Brendan Rodgers should take a cue from Diego Simeone's Atlético Madrid, a bruising side who routinely get away with legions of yellow card-worthy tackles simply because they overwhelm the referee with them. They set those kind of fouls as the norm, so only exceptionally violent or late ones get punished. Neymar in particular has shown a propensity to get rattled when consistently subjected to physical play that referees overlook, and wining up their best player is the smart way to go.