Here are the standout games from the action to come.
Tuesday, March 11th
Liverpool vs PSG (1-0 after the first leg) - 21:00 CET
If someone told you when Liverpool and PSG were drawn against one another that Arne Slot's side would take a 1-0 lead to Anfield, you'd consider them big favourites to progress, but that's not really the case after how the first-leg panned out.
While Liverpool did win, they were completely outplayed by their French opponents, who played some stunning football and had 27 attempts to the Premier League side's two, but just couldn't convert their chances.
That was largely because of one of the best goalkeeping performances you'll ever see from Alisson, who made nine saves, but the chances of him producing such heroics again are slim; if PSG can dominate like they did in Paris, they could easily turn things around and secure a spot in the quarter-finals.
Liverpool will surely step things up a gear in front of a raucous home crowd but even if they do, seeing off Luis Enrique's men won't be easy with Ousmane Dembele still in the form of his life - he bagged a brace at the weekend - and Kvicha Kvaratskhelia showing in the first leg that he can cause Trent Alexander-Arnold huge problems.
There have been countless unforgettable European nights at Anfield over the years, and it feels like this will be another one.
Wednesday, March 12th
Atletico Madrid vs Real Madrid (1-2 after the first leg) 21:00 CET
Real Madrid could have been heading across the city to the Metropolitano Stadium with a two-goal lead had they not missed a huge chance at the end of the first leg, but instead, this tie hangs in the balance.
Los Blancos just about deserved their win on home turf thanks to a strong second-half performance in particular, but there wasn't much between the two sides and Atletico Madrid will fancy their chances of turning things around at a ground where they've avoided defeat to their rivals in their last three meetings, winning two of them.
Their home record in the Champions League is extremely impressive. The club have lost just one of their last 14 games in the competition to be held there, and they haven't lost a Champions League knockout match at home since March of 1997.
That being said, Real Madrid have never lost a knockout tie under Carlo Ancelotti after losing the first leg and will be desperate to maintain that record in what is set to be the Italian's last chance to add another European trophy to the cabinet before he departs in the summer.
The stakes couldn't be higher in a derby that couldn't be fiercer. Bring it on.
Thursday, March 13th
Athletic Club vs AS Roma (1-2 after the first leg) - 18:45 CET
Athletic and Roma headed into this tie as two of the favourites to win the Europa League, and that remains the case after a first-leg that kept both sides' chances very much alive.
After being the better side in the first half of the first leg, Athletic took the lead early after the break and looked likely to head back to Spain ahead, but Roma rallied to equalise shortly after before getting a last-gasp winner.
With the Serie A side leading by a goal but the Spanish club having home advantage, this really could go either way now. Roma are in better form having won their last six matches, but the hosts have won every Europa League match played on home turf this season and they've beaten their opponents by at least a two-goal margin in three of them.
Everything suggests that this will be a hotly-contested, high-quality, high-drama affair between two sides that know they'll have a huge chance of going all the way if they can just clear this hurdle.
Tottenham vs AZ Alkmaar (0-1 after the first leg) - 21:00 CET
One of the biggest upsets of the Europa League first-legs came in Alkmaar, where AZ claimed a very much deserved 1-0 win against Tottenham.
It may seem at face value that Spurs can overturn a one-goal deficit on home turf without too much trouble, but that won't be the case going by how things went in the Netherlands. It was an affair dominated by the Dutch side, who really should be heading to London with a bigger lead under their belt.
It can't be overstated how important it is for hosts that they produce a better performance on Thursday; winning the Europa League is the last chance they have this season of finally ending their trophy drought, and it could well be the last chance they have of ensuring that they'll be playing European football next season given they're down in 13th in the league.
Failing to lead them to a trophy and/or European qualification would make Ange Postecoglou's immediate - let alone long-term - future at the club very much uncertain, so this match really couldn't be any bigger for the manager or his club.
Manchester United vs Real Sociedad (1-1 after the first leg) - 21:00 CET
Ruben Amorim isn't under quite as much pressure as his Tottenham counterpart, but with the Europa League also being Manchester United's only chance of a trophy this season now, this clash with Real Sociedad will be the biggest yet of the manager's Old Trafford tenure.
It's massive for Real Sociedad too, who now look unlikely to qualify for the Champions League or even the Europa League through their LaLiga position after losing six of their last eight league games.
Which club will get a much-needed win is tough to predict with how tight the first leg was. Across the 90 minutes, both sides had 13 shots and racked up similar xG totals - 1.46 for Real Sociedad and 1.16 for Manchester United.
It's easy to see this turning into a cagey affair given the importance of it to both sides, especially after Amorim showed against Arsenal that he's willing to be more pragmatic, so this could well go the distance.