FC Porto have already progressed as Dynamo Kiev cannot finish above them in the table. The two teams could be level on points but Porto have the superior head-to-head record - a factor that ranks ahead of goal difference when separating teams.
PSG have a five-point cushion over Dynamo and will qualify with a draw in Ukraine in two weeks' time.
Dynamo Kiev must win both their remaining games, and almost certainly require PSG to lose at home to Porto on matchday six. If PSG draw with Porto in that final game, putting them level on points, Dynamo will only go through if they have beaten PSG 3-0 or by more than three goals to be then placed second on head to head.
Dinamo Zagreb have already been eliminated.
Schalke will qualify with a home win over Olympiakos on matchday five. If they do not win they will need a point at the very least on the final day at Montpellier.
Arsenal would be through with a win over Montpellier in their next fixture, coupled with an Olympiakos defeat in Germany. But if Arsenal fail to win at home to the Ligue 1 side then the final matchday trip to Olympiakos is guaranteed to be a decider.
Olympiakos must beat either Schalke or Arsenal to have any hope of going through.
Montpellier have already been eliminated.
Malaga are already through in their debut Champions League campaign.
AC Milan, Anderlecht and Zenit St Petersburg are seperated by just two points, with the Rossoneri currently second. Milan will definitely qualify with a win in Anderlecht in two weeks time and a draw at home to Zenit.
Anderlecht must avoid defeat at home to Milan to remain in the Champions League and a point against Milan would require them to beat Malaga and hope there is no winner between Milan and Zenit. If Anderlecht beat Milan they only need a point in Malaga to guarantee finishing above the Serie A giants, but may need a victory in Spain to hold off Zenit.
Zenit may still be able to qualify if they do not win at home to Malaga but it would require Anderlecht to take points off Milan. Zenit would still miss out with two wins if their Belgian opponents achieve the same results and six points would, at this stage, seem to be the minimum needed for the Russian club to avoid elimination.
Borussia Dortmund need a point at Ajax to book their passage with a game to spare. If Dortmund lose to both Ajax and to Man City their fate would be decided by the result of the Ajax vs Real Madrid game on matchday six.
Real Madrid will be through if they beat Man City and Ajax do not pick up three points against Dortmund.
Ajax may not even qualify with two victories and would likely lose out to Real Madrid if head to head is required. If they do not win at home to Dortmund they will be eliminated by any positive result for Real against Man City.
Man City have to win both of their remaining fixtures. There is the possibility that all four teams could finish on eight points and the group be decided on goal difference, which would leave Dortmund in a very precarious position as they would have to lose both matches for this outcome to happen and therefore damage their goal difference. Real would likely be secure in that outcome.
Another group which is exceptionally tight but Chelsea and Shakhtar Donetsk may feel they have a slight edge due to both of them having a remaining fixture against FC Nordsjślland.
Juventus vs Chelsea on matchday five will have a major influence on the qualifiers and a defeat for Juve would likely confirm a drop into the Europa League. Holders Chelsea will guarantee their place in the next round by winning in Turin. Shakhtar Donetsk will qualify with a win at FC Nordsjślland in two weeks if Chelsea beat Juventus.
If Juve claim a draw against Chelsea, the Serie A side would be guaranteed to qualify by winning at Shakhtar in the final round of games.
If Shakhtar do not beat Nordsjślland their game against Juve is guaranteed to be in effect a qualification play-off.
Should Chelsea lose to Juve, Roberto Di Matteo's side can only qualify by beating Nordsjślland and relying on Shakhtar to win at home to Juve - this assumes Shakhtar have also beaten Nordsjślland.
If Nordsjślland take points off Shakhtar on the next matchday the group has a completely different complexion, though the Danes have themselves been eliminated.
Valencia and Bayern Munich play each other next time out in a match which will impact the chances of both teams, and that of BATE Borisov. If that game finishes in a draw and BATE win at home to Lille, just a point will separate the three teams.
Valencia will go through if they beat Bayern regardless of BATE's result due to their head-to-head record with the Belarusian club. If Bayern beat Valenica then all three clubs could still finish on 12 points, and the positions would be decided on goal difference only in games between those three teams.
If BATE beat Lille and Bayern lose to Valencia, BATE would need a draw at the Allianz Arena to finish second on head to head. If Bayern avoid defeat against Valencia, BATE will have to win both of their remaining games to be in with a chance.
Lille have been eliminated.
Barcelona need two points to be assured of progression.
Celtic will be through with a win at Benfica, or a score draw if Spartak Moscow do not beat Barcelona.
Benfica will be out unless they beat Celtic or draw 0-0. With the goalless draw, they would then have to win at Barcelona, hope Celtic are defeated at home to Spartak and turnaround the goal difference with the SPL side. If Benfica beat Celtic they will only need to match the Bhoys result on the final day - unless Spartak have shocked Barcelona.
Spartak have to claim a minimum of four points to have a chance of qualifying, but will likely need to win both matches.
Manchester United are already through with the only perfect record in the Champions League after four matches.
A point separates the other three teams, and Cluj may need to win at home to Braga to be in with a chance as they visit Old Trafford on the final day. If Braga lose to Cluj on matchday five they will be eliminated.
However, if Braga take anything from their game at Cluj they may feel they are the favourites to finish second, with a home match against Galatasary to round off the group.
But with Manchester United likely to rest players in the final two matches, the Turkish club feel confident of a positive result at home to their Premier League counterparts - which could give the group a different look going into December.
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