This week the Champions League group stages come to a close. While several groups already have the top spots claimed, there's only one group left in which second place is not still up for grabs. This means a wild and confusing final two days of matches.
Allow us to guide you through each group and hopefully explain the various scenarios that could play out. Just a reminder, the first tiebreaker this year is head-to-head goal differential between the teams in question.
Manchester United are through to the next round but haven't secured first place. A win over Shakhtar Donetsk would do the trick. Shakhtar, who currently sit second, would win the group with a win at Old Trafford and eliminate Bayer Leverkusen. If Shahktar draws, Bayer Leverkusen need a win over Real Sociedad to leap over the Ukrainian side into second place. If Shahktar loses, Leverkusen will advance with a win or draw against La Real.
Real Madrid have clinched the group's top spot so that leaves Juventus and Galatasaray to rumble for second place. Juve are in the driver's seat with a two point lead over the other two sides. A win or draw by Juve against Galatasaray would be enough to secure second place. Galatasaray must defeat Juventus to advance; any other result would eliminate the Turkish side.
Paris Saint-Germain have won the group so they are through to the knockout round. Benfica and Olympiakos are tied on seven points, with Olympiakos holding the tiebreaker thanks to head-to-head goal difference. Olympiakos must simply match or better Benfica's result on the final day to advance. Benfica need a win over PSG combined with a Benfica loss or draw against Anderlecht to advance.
Bayern Munich and Manchester City have claimed both qualification spots in Group D but first place is still up for grabs. City's path to first place requires them to win by three goals at the Allianz Arena or for Bayern to concede more than one away goal. For example, if City wins 3-1, Bayern take first place. If City were to win 4-2, they would finish atop the group.
This group is extremely tight with Chelsea (8 points), FC Basel (7 pts.) and Schalke 04 (6 pts.) currently sitting first through third. Chelsea are guaranteed a spot in the next round, but whether they'll finish first or second is yet to be determined. Chelsea's path to the spot is fairly simple though as they simply must match or better Basel's result against Schalke to finish first. Basel would take first place with a win over Schalke, combined with a Chelsea loss or draw against Steaua Bucuresti OR if Basel draws and Chelsea loses, Basel would take first place with the tiebreaker.
Basel would at least claim second place with a win or draw against Schalke, while the Germans must defeat Basel to advance.
Arsenal currently sit in first place, three points clear of Napoli and Borussia Dortmund. A win or draw by the Gunners against Napoli would secure first place in the group for them. Dortmund would win the group via a tiebreaker with a win over Marseille and a loss by Arsenal. Napoli would win the group if Dortmund loses and they defeat Arsenal by three goals or more.
But wait! There's more!
There's a chance that all three teams could end up tied on 12 points if Napoli defeats Arsenal and Dortmund wins. Oh joy. In this scenario, Dortmund finishes first unless Napoli defeats Arsenal by five goals, which would give Napoli the tiebreaker over Dortmund. Napoli would have to defeat Arsenal by three goals to take over second place from Arsenal, otherwise the Gunners would finish second.
Atlético Madrid has clinched first place in the group, so their work is done. Zenit St. Petersburg currently sit in second, one point ahead of FC Porto. Zenit would advance with win over Austria Vienna, while Porto would advance with a win over Atlético combined with a Zenit draw or loss. If the two teams end up tied -- this happens if Zenit loses and Porto draws -- Zenit would advance thanks to the tiebreaker.
Barcelona are safe in first place as they hold the tiebreaker over everyone in the group. So that leaves second place up for grabs between AC Milan and Ajax, who just happen to be playing one another. AC Milan just need to win or draw to advance, while Ajax must win to take over second.