Liverpool host Napoli in their final game of the group stages.
If they beat the Italian side 1-0, they will advance to the knockout stages of the Champions League.
However, if they win 2-1, they won't qualify for last-16 because of an away goals rule.
But, if Liverpool win by two clear goals, they will reach the knockout stages.
And, if PSG lose or draw against Red Star, Liverpool will go through if they win their tie.
It will be a tense night against Napoli at Anfield on December 11.
Here's BT Sport's attempt to explain the permutations:
*Deep breath, Liverpool fans, here's what needs to happen*
IF: Liverpool beat Napoli at Anfield 1-0 they go THROUGH ✅
IF: Liverpool win 2-1 they go OUT on the away goals rule ❌
IF: Liverpool win by two or more goals they are THROUGH ✅
It's not over yet! pic.twitter.com/
https://www.sportsjoe.ie/football/liverpool-champions-league-last-16-186287