The Champions League, that most coveted of European trophies, has already reached the halfway stage. But in every group, there is still plenty to play for.
Tuesday and Wednesday will see a full programme of matches across each of the eight groups, as 32 teams aim for the points that will move them a little closer to the knockout stages. But what team is looking good for a challenge, and what team is already looking likely to miss out on glory this year?
Starting with the squads that will get the round underway Tuesday, we take a look at every group and how it stands after three games, highlighting the most enticing clashes to look out for across the Continent.
Shakhtar Donetsk vs. Bayer Leverkusen
Having endured a tough start to their Champions campaign, Leverkusen sprung back into life with a 4-0 dismantling of Shakhtar to regain a place in the knockout stages. The Ukrainians, however, will be desperate for revenge and will be a force to be reckoned with in front of their own fans.
Real Sociedad vs. Manchester United
The Red Devils' unbeaten start to Group A has helped to allay a less than impressive Premier League campaign so far. Against a Real Sociedad team that has failed to pick up a single point, David Moyes' charges will be hot favourites even away from Old Trafford.
Juventus vs. Real Madrid
Without a doubt, this is one of the most tantalising fixtures of the entire week. Italian champions Juventus with an on-fire Carlos Tevez host a Real Madrid side slowly finding their feet under Carlo Ancelotti. Cristiano Ronaldo has been in devastating form for the Merengue, which start as slight favourites to preserve their perfect record.
Copenhagen vs. Galatasaray
With the blockbuster clash in the other half of the group, few outside of Denmark and Turkey will be paying too much attention. But underestimate Galatasaray at your own peril: A win away Tuesday, coupled with a loss for Juventus, would leave their Turin counterparts virtually eliminated from the knockout stages.
Paris Saint-Germain vs. Anderlecht
French champions PSG have quite simply been untouchable in the first three rounds, winning every game with the goal-happy Edinson Cavani and Zlatan Ibrahimovic. The latter smashed four as Anderlecht were humiliated 5-0 at home in the last round, and it is difficult to see the Parisiennes going lightly Tuesday.
Olympiacos vs. Benfica
With half of Group C played, Olympiacos and Benfica are deadlocked on four points as they fight for the right to accompany PSG into the last 16. Tuesday's clash in Piraeus will go a long way to defining that second place, although neither team will be out of the running just yet.
Manchester City vs. CSKA Moscow
Having demolished Norwich 7-0 at the weekend, Manchester City will certainly be on a high going into the key clash against Russian giants CSKA Moscow. If Manuel Pellegrini's men win, they will be guaranteed a place in the knockout stages. It will be interesting to see how Costel Pantilimon performs in goal ahead of Joe Hart.
Viktoria Plzen vs. Bayern Munich
A frightful mismatch on paper, and it might just prove to be the same out on the pitch. Bayern are among a select group of teams yet to drop a point on their campaign, and few would bet against seeing a repeat of the 5-0 drubbing handed out to Viktoria in the previous fixture.
Basel vs. Steaua Bucharest
Having pulled off a massive upset over Chelsea in the first round, Swiss underdogs Basel have a real chance of advancement. Victory over bottom side Steaua would fire them into the top two, leaving Murat Yakin's men with a pair of finals in order to repeat the achievement of 2011-12 and make the knockouts.
Chelsea vs. Schalke 04
The two Group E frontrunners are widely tipped to qualify, but they will have to be careful with Basel hot on their heels. Whoever wins at Stamford Bridge will have one foot in the next round, while the loser will have to slog it out until the very last day to ensure their place.
Borussia Dortmund vs. Arsenal
One of the Champions League's tightest and most intriguing groups enters a vital stage. Borussia Dortmund, Arsenal and Napoli are all tied on six points after three games, and the winner of Wednesday's clash will have the chance to put a little daylight behind them at the top.
Napoli vs. Marseille
The Italian side, meanwhile, have the duty of beating pointless Marseilles to keep touch at the head of the table. An unfortunate 2-0 defeat to Arsenal put a dent in the Napoli challenge, but with the likes of Gonzalo Higuain, Jose Callejon and Duvan Zapata, the club have the ability to score from across the pitch.
Zenit St. Petersburg vs. Porto
Brazil international Hulk once more faces off against his former club, after failing to hit the net in Portugal but still coming out as the winner against 10-man Porto. The physical forward has only managed one goal so far in the Champions League and needs to find form if the Russians are to hold on for a place in the next round.
Atletico Madrid vs. Austria Wien
Perfect in the UCL and taking down all comers domestically, Diego Simeone's Atletico have been the revelation of the season thus far. Their success has been based on the attacking trident of Diego Costa, David Villa and Koke, a trio that should have far too much firepower for Group G stragglers Austria Wien.
Ajax vs. Celtic
After a terrific 2-1 win two weeks ago in Parkhead, Celtic still have a fighting chance of making the last 16. Ajax will be out for revenge Wednesday, but with just one point from their three fixtures so far it is difficult to see how the historic Dutch giants can regroup and challenge for qualification.
Barcelona vs. Milan
Manager Gerardo Martino has taken to Barcelona like a duck to water, as has Neymar. Even with Lionel Messi far from his best, the young Brazilian has stepped up and taken the spotlight alongside an almost unrecognisably impressive Alexis Sanchez. This depth of attacking talent should be too much for Milan, which ground out a draw last time against the Catalans.