After a thrilling night of action on Tuesday, which saw Barcelona and Paris Saint-Germain take significant steps towards the next knockout stage, Wednesday sees four of Europe's biggest clubs in action.
Current holders Bayern Munich travel to North London to face a buoyant Arsenal team, who are jubilant after disposing Liverpool from the FA Cup.
The other game sees a classic tie as the fallen giants of AC Milan take on the surprise package of La Liga this season, Atletico Madrid.
All four teams will have realistic ambitions of reaching the last eight of the competition.
Arsenal will feel well equipped to battle their German opposition who are running away with their own domestic league. The Gunners faced the always impressive Munich side last year in the competition, and were edged out on away goals after being defeated 3-1 at home, per Phil McNulty of BBC Sport.
McNulty explains how confident Arsenal are going into the match, quoting Theo Walcott saying: "We've learnt from so much experience we've had in the last year, ever since that Bayern Munich result, really, it's changed the whole club."
Milan face an Atletico team in hot form, but the Spanish team's manager Diego Simeone will not be taking the multiple-times Champions League winners lightly, despite their shocking domestic form. Simeone said: "I expect the best Milan. They have dangerous players on each side, with a good game between the lines inside."
So which player will be each team's catalyst?
It has all gone a bit strange for the diminutive German of late. After a blistering start in an Arsenal shirt after his transfer from Real Madrid, his recent performances have been rather average.
The playmaker only has four goals to his name in the Premier League this season, per Squawka, and you would expect a player of his standard to have more.
But despite this, Ozil will be the main player in any success for the Gunners against this Munich side. They will need his guile and flair to provide the ammunition, especially with Theo Walcott spending an extended period on the sidelines due to injury.
Without Aaron Ramsey, the onus is on Ozil to provide a goal or two and improve his work-rate, but whether he is actually that type of player is up for debate.
He could be viewed as the ultimate "luxury player" but his record before this season speaks volumes toward what he can achieve.
Arsene Wenger's side have a similar opportunity to that of Manchester City, who had the chance to slay one of the really established names in world football against Barcelona. Where City failed last night, Arsenal and Ozil might succeed.
Arjen Robben—Bayern Munich
Bayern Munich have not even conceded double figures in the Bundesliga this season, having only shipped an incredibly small total of nine goals, per Squawka. But the real danger comes from their illustrious attacking midfield that features some of the greatest talent in the world.
And they do not come much more dangerous than Arjen Robben of Holland. The former Chelsea player may not start in every match due to a succession of injuries, but his record is still exceptional.
In 16 league games this season he has scored seven times and created 32 chances, per Squawka, a fantastic record when you consider that in many of those matches he has only come off the bench.
Robben is still one of the trickiest wide players in Europe and if he gets the chance to do Arsenal any damage he will take the opportunity.
You have to fear for Per Mertesacker in particular if the Dutchman comes inside and runs at him.
Whatever happens, Wenger will be paying special attention to the player and will attempt to squeeze him out of the contest.
But that is easier said than done, and whether Arsenal's flamboyant midfield can show the courage to keep up with him is going to be a huge question in this game.
Adel Taarabt—AC Milan
Milan have very much been "doing a Manchester United" in Italy this season, as they watch their traditional rivals leave them for dust.
Their chances of progressing here, against the bright young hopes of Spanish football in Atletico, are slim. But a surprise could be in store as the club prepare to give new signing Adel Taarabt his debut in the Champions League.
English league fans will know all about Taarabt for his time at Tottenham Hotspur, QPR and Fulham. He was one of the most highly rated young talents in Europe at one stage, but his form evaporated over a long period of time.
Now he has a huge opportunity at a massive club, and there is a chance he might take it. Taarabt scored on his Milan debut in a 3-1 defeat at Napoli, per WhoScored.com, a signal that good things may be around the corner.
The 24-year-old Moroccan has been looking for a stage to showcase his ability, and the San Siro will be the perfect arena for this.
Can he really step up in the biggest club competition of them all? We will have to wait and see.
Diego Costa—Atletico Madrid
He is without question one of the hottest strikers on the planet today. Diego Costa has been pure electricity this season, scoring for fun and decimating opponents.
His 2013-14 record is outstanding: He now has 25 goals in 26 games, with four assists, per WhoScored.com.
If Costa turns up in Milan with his shooting boots on, there is little chance the Italian side will be able to contain him.
As his stock rises it is likely to be Costa's last season with Atletico, with a megabucks deal from one of Europe's elite clubs surely forthcoming.
His perfect parting gift would be to fire his current club toward the last stages of this season's Champions League, and getting further than fierce local rivals, Real Madrid.
Milan's poor form will play into Atletico's hands, and you cannot predict anything other than a comprehensive victory for the Spanish side.
How many goals the brilliant Brazilian will score on Wednesday night is anybody's guess.