Manchester United head into their final Champions League 2020-21 group stage fixture top of Group H, but they still face a tough task to ensure they qualify for the last 16.
Man Utd, Paris Saint-Germain and RB Leipzig all sitt on nine points apiece in Group H, with the race for knockout stage qualification going right down to the wire.
Goal has what you need to know about what Man Utd need to qualify for the next stage of the Champions League.
What result do Man United need to qualify for the Champions League last 16?
Man Utd need at least one point - or a draw - away against RB Leipzig to progress to the knockout stage.
This is due to Man Utd having a superior head-to-head against Leipzig, who they beat 5-0 in the first leg.
They cannot qualify if they lose to RB Leipzig, even if PSG lose their final game against Istanbul Basaksehir..
Losing to RB Leipzig will see Man Utd drop down to the Europa League, and Leipzig and PSG progressing.
This is because Neymar's stoppage-time goal in Man Utd's 3-1 loss to PSG means that the French giants hold the superior head-to-head record between the two clubs. So in the event of both Man Utd and PSG losing, PSG will progress based on their head-to-head.
If both Man Utd and PSG draw their final games - with the duo plus RB Leipzig all finishing on 10 points - then Man Utd would win the group, PSG would finish second and RB Leipzig would enter the Europa League.
The Red Devils scuppered the opportunity to qualify for the knockout stages with an extra game when they lost to PSG at Old Trafford in matchday five.
Champions League 2020-21 knockouts: What does each team need to qualify for last 16?
Ole Gunnar Solskjaer's team needed just a point against the French heavyweights to qualify, but the defeat means that they will now absolutely need at least a point to keep their Champions League dreams alive.
PSG are in pole position to qualify for the Champions League last 16, and need just a point at home to Istanbul Basaksehir to ensure progression.
They will top the group with a win against the Turkish side at the Parc des Princes.
Solskjaer has called for his United side to go into Tuesday's game at the Red Bull Arena looking for a victory, saying: "You can’t sit back and hope for a 0-0 draw. That’s not in our genes, it’s not in the team’s genes, it’s not in the club’s genes, we want to go out there and win a game.
"We showed that against PSG that we wanted to go out and create chances and we’ll do that again."