Four teams have already booked their spots in the Champions League round of 16, the likes of Ajax Amsterdam, Bayern Munich, Juventus and Liverpool, who are the only team to have sealed their place as group winners with games to spare.
But with matchday 5 upon us, who are the other teams that could join the quartet in the round of 16?
No fewer than 13 teams have a chance to confirm their places at the end of this round of matches on Wednesday,
Here is all you need to know about the giants like Barcelona, Manchester United, Chelsea, Real Madrid and Inter, who are set to battle for their tickets to the knockout stages of the 2021/2022 Champions League season.
Tuesday, 23 November
Groups E to H take to the pitch on Tuesday led by Group E leaders, Bayern Munich, who just need to avoid defeat in Kyiv when they take on their host Dynamo Kyiv to pick up their ticket as group winners.
The Bavarians lead the group on 12 points, six points above their nearest challengers, Barcelona, who can join them in the round of 16 with a win over Benfica at Camp Nou.
Manchester United looking for fresh start at Villarreal
Things are quite interesting Group F, where all four teams are in contention for a place in the knockout round.
Manchester United are in search of a fresh start after Ole Gunnar Solskjaer was sacked on Sunday.
They go head-to-head with Villarreal at the Estadio de la Ceramica with another former player Michael Carrick now in charge.
Both teams are level on 7 points and need a win to seal their a place in the next round.
United need a win over the Yellow Submarines to book their place, while their hosts, Villarreal, will qualify with a win over the Red Devils as long as Atalanta, who must win at Young Boys to keep hope alive, fail to take all three points in Switzerland.
Young Boys are also in contention for a place in the round of 16 but must beat Atalanta to still have a chance.
Salzburg, Lille in head-to-head battle
Only Salzburg can qualify from Group G on matchday 5 but must beat LOSC Lille in France to do so tonight. Lille and Wolfsburg will wait until matchday 6 but will do themselves a favour with wins. Sevilla are out of contention but can still make it to their favourite competition, the Europa League with a win over Wolfsburg.
For Group H, Juventus are through but there is still the little matter of who tops the group and the Italians will travel to Stamford Bridge looking for the one point that will guarantee them top spot as group winners. They face Chelsea, who will join the Old Lady if they avoid defeat at home or Zenit fail to get a win at Super Eagles' Bonke Innocent's Malmo.
Wednesday 24 November
The biggest match of matchday 5 will see Manchester City host PSG at the Etihad on Wednesday in Group A. Separated by a point, both teams could qualify with a win or if they avoid defeat and Club Brugge fail to win at home to RB Leipzig.
Atletico, Porto and AC Milan battle for one ticket
Group B is just a battle for who joins already qualified group winners, Liverpool, in the round of 16.
The trio of Porto, Atletico Madrid and AC Milan are all within a chance of joining the Reds, but Porto must beat Liverpool at Anfield and hope that Atletico lose at home to Milan, who themselves must win in Spain to stay in serious contention heading into the final round of games.
Ajax are through but still need a point at Besiktas to win Group C, while it is a straight fight between Borussia Dortmund and Sporting CP for the second spot. Both teams need a win, but Sporting must beat Dortmund by at least two or more goals.
It's all to play for in Group D
Finally, Group D is also quite open, all the teams have at least a chance to pick a ticket. Real Madrid have to redeem their image against Sheriff with a win to pick a round of 16 ticket and will win the group should Inter fail to win against Shakhtar Donetsk.
Italian champions Inter need a win as well to go through as long as Sheriff fail to beat Real, while Shakhtar are condemned to win at San Siro to stay in contention.