The latter weeks of the Champions League group stages can often be rather stale. This year, however, we seem to be getting treated to more big game matchups and several tightly competitive groups.

On a night where several teams could guarantee progression and some could secure their place as the number one team in a group, there was so, so much to play before. A shade inferior to that, though, was the teams looking to keep their hopes alive of playing European football after Christmas at all.

Some games were played in near-arctic conditions and, due to rescheduling, only six games were left at the standard 7:45pm kick-off time. Even before the majority of matches had started we had witnessed a miraculous comeback and a monumental upset, it was at that point that we knew we could be in for another special night in the Champions League.

Plenty went on and it was hard to keep up with all of it at times so we have handily covered the key bits here.

Bayern's Nightmares Continue

Carlo Ancelotti

Carlo Ancelotti's troubled start to life at Bayern Munich continued as his side were beaten, and outplayed, by FC Rostov.

Losing any chance of winning their group as a result, Bayern played without intensity and look a team short of an identity in the wake of Pep Guardiola's spell at the club.

A defeat to Borussia Dortmund last weekend was a concern, but this is now the beginning of a crisis.

Goodbye Celtic

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No amount of Brendan Rodgers press conferences or 'character' could save Celtic against Barcelona.

As good as they have been for small segments of their Champions League campaign, it was the two games against Borussia Monchengladbach that really cost the Scottish giants and they must wait another year for a chance of Champions League knockout football.

Besiktas in with a sniff

A fan waves a Besiktas flag before the Turkish Super League soccer match between Besiktas and Bursaspor at Vodafone Arena, the new stadium of Besiktas soccer team, in Istanbul

Few games in world football will be as exciting as Besiktas' match with Benfica.

3-0 down with just over half an hour to go, Besiktas' fans could have been forgiven if they thought it was all over. It was not over, however, and a stunning comeback to claim a draw leaves the Turkish club in with a chance of qualification.

Atleti Attackers

Simeone

Atletico Madrid have a different dimension to them this season. Partly down to a simple change in approach and partly down to the arrival of Kevin Gameiro, Diego Simeone's side look all the more complete as a result.

Could this be the step that pushes the noisiest neighbours in world football to European glory?

Finishing top isn't all that

Manchester United v Arsenal - Premier League

Whether down to the change in Champions League seeding or just a weird series of events, finishing top of your group in the Champions League is not the guarantee that it once was.

Manchester City, Real Madrid, Bayern Munich and Porto currently reside second in their groups, meaning that a few group winners could be getting a rather scary last 16 tie.