Barcelona, Besiktas, Manchester City and Tottenham Hotspur are all through as group winners.
Read on for a full schedule and viewing details as well as a full explanation of the permutations for each group.
Indeed, it may turn out that only two qualifiers come from outside that elite, with Turkish champions Besiktas already through in Group G and only one of Basel or CSKA Moscow likely to advance in Group A.
A defeat may also be enough, but if Basel beat Benfica, the group would be decided on a three-way head-to-head as United, CSKA Moscow and the Swiss side would all have 12 points.
With both PSG and Bayern through, and Bayern needing a four-goal win to pinch top spot, this could easily have been a drab affair with both sides going through the motions.
Basel made it through to the knockout stage for the first time since 2011-12.it was well-beaten away to Manchester United in the opening match day and then suffered a slightly unfortunate 2-1 home loss to CSKA, but it has been generally impressive in this campaign.
Benfica are yet to pick up a single point and will therefore finish bottom of the group no matter what happens on Tuesday. Powered by a front three of Neymar, Edinson Cavani and Kylian Mbappe, PSG had set a group-stage record of 24 goals before kick-off at the Allianz Arena, but were comfortably seen off by the five-time champions despite holding on to seal top spot in Group B.
So far, 11 matches have been won by a margin of four goals or more.
Celtic secured the Europa League spot in the group despite losing 1-0 at home to Anderlecht, on a Jozo Simunovic own goal. A point will confirm European football in the new year for the Scottish side, whilst Anderlecht can leapfrog them into third on goal difference providing they win 3-0.
Chelsea are two points clear at the top and will finish first with a win over Atletico Madrid or if Roma fail to beat Qarabag.
Roma knew they would go through from Group C with a win, which they got, although they could only edge out Qarabag of Azerbaijan 1-0 at the Stadio Olimpico with a Diego Perotti effort in the second half.
Atletico can still qualify, but it's unlikely.
Lionel Messi was left on the bench at a sparsely populated Camp Nou as Paco Alcacer headed the hosts in front and Jeremy Mathieu then scored an own goal against his old side. If both Athletico and Roma draw, Athletico will progress with a superior head-to-head record.
Juventus clinched its place in the last 16 with a 1-0 victory away to Olympiakos. A further 15 matches have seen three-goal victories, meaning nearly exactly a third of the group games to date have been decisively one-sided.