The reverse fixtures of the opening day of the Champions League group stages come into play on Matchday 5 on Tuesday and Wednesday.
After a three-week hiatus, Champions League action returns with teams from Group E, Group F, Group G and Group H battling it out for a place in the last 16 on Tuesday.
The most crucial of those matches on Tuesday will be Arsenal's home game against Dinamo Zagreb, with Arsene Wenger's men needing all three points to keep their hopes of qualifying for the knockout stages alive.
In over 15 years, Arsenal, struggling for form and injuries at the moment, haven't failed to make it past the group stages of the Champions League, but after three poor performances out of four matches, their future in the competition this season looks dicey, at best.
While Arsenal will look to hang on by their fingernails, some of the other big teams will want to seal their place with a bit of style, with Bayern Munich hosting Olympiakos â€“ if the two teams play out a draw at the Allianz Arena, then both will go through, with Arsenal left scrapping for the Europa League place -- while Barcelona play Roma at the Camp Nou, after mauling Real Madrid.
Barcelona were irresistible against Real Madrid on Saturday, with Neymar and Luis Suarez, in particular, having fabulous games. With Lionel Messi also making a return from injury, this match looks like going one way, even with Barca needing just a draw to qualify as group winners.
In Group G, Chelsea, having returned to winning ways in the English Premier League, will want to stay on the tails of FC Porto, when Jose Mourinho's men travel to Israel to play Maccabi Tel Aviv. Chelsea were comfortable winners in the reverse fixture at home, and Mourinho will demand a similar result, a result which might end up being enough for them to qualify for the round of 16.
The pick of Wednesday's action is Juventus vs Manchester City. Both teams are well placed in the group, with City on nine points and Juve a point behind. Sevilla, in third, are a further five points adrift, and a draw looks like being the best result for both teams in Turin.
In Group A, Real Madrid will want to bounce back from the galling defeat to Barcelona, when they play Shakhtar Donetsk away, but all eyes will be on the other match in the group, as Zlatan Ibrahimovic returns home with Malmo hosting PSG. Victory will be enough for both PSG and Real Madrid to go through to the next round.
Another match to watch out for on Wednesday will be the Group B clash between Manchester United and PSV Eindhoven. Group B is set up nicely at the moment, with all four teams still in with a chance of qualifying. Manchester United are top of the group with seven points, but PSV and Wolfsburg are right behind them on six, with CSKA Moscow a further two points behind.
Louis Van Gaal's men will be determined to gain some revenge from a Matchday One defeat at PSV, and the way Manchester United are playing at the moment, that certainly looks possible.
UEFA Champions League 2015 schedule: Matchday 4: Tuesday, 24 November: Group E: BATE Borisov vs Bayer Levekusen (6 pm CET, 10.30 pm IST, 5 pm GMT, 12 pm ET) at Borisov Arena.
Barcelona vs Roma (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) at Camp Nou.
Group F: Arsenal vs Dinamo Zagreb (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) at Emirates Stadium.
Bayern Munich vs Olympiakos (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) at Allianz Arena.
Group G: FC Porto vs Dynamo Kyiv (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) at Estadio do Dragao.
Maccabi Tel Aviv vs Chelsea (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) at Sammy Ofer Stadium.
Group H: Zenit St. Petersburg vs Valencia (6 pm CET, 10.30 pm IST, 5 pm GMT, 12 pm ET) at Stadion Petrovskiy.
Lyon vs Gent (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) at Stade de Gerland.
Wednesday, 25 November: Group A: Malmo vs Paris-Saint Germain (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) at New Stadium in Malmo.
Shakhtar Donetsk vs Real Madrid (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) at Arena Lviv in Lviv.
Group B: CSKA Moscow vs Wolfsburg (6 pm CET, 10.30 pm IST, 5 pm GMT, 12 pm ET) at Arena Khimki in Khimki.
Manchester United vs PSV Eindhoven (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) at Old Trafford.
Group C: Astana vs Benfica (4 pm CET, 8.30 pm IST, 3 pm GMT, 10 am ET) at Astana Arena.
Atletico Madrid vs Galatasaray (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) at Vicente Calderon.
Group D: Juventus vs Manchester City (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) Juventus Stadium.
Borussia Monchengladbach vs Sevilla (8.45 pm CET, 1.15 am IST, 7.45 pm GMT, 2.45 pm ET) at Borussia Park.
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