Here are the four standout second-leg clashes:
Tuesday, February 18th
Bayern Munich vs Celtic (2-1 after the first leg) - 21:00 CET
It was a roaring atmosphere at Celtic Park last week as the Scottish champions scored late to keep themselves in the tie against German giants Bayern Munich.
Harry Kane and Michael Olise gave the visitors a commanding lead before Daizen Maeda popped up to halve the deficit late one, giving Celtic a puncher's chance going to the Allianz Arena.
Under Vincent Kompany, Bayern have won each of their four Champions League games at home, a record-equalling that of Hansi Flick and Jupp Heynkes, but they will be under pressure to make sure they are not upset at home.
Keeping the likes of Kane and Jamal Musiala, who signed a new deal with Bayern until 2030 on Friday, will be key if they are to provide some drama in Germany, but don't count them out just yet - this could be a night to remember for the Bhoys.
Wednesday, February 19th
Real Madrid vs Manchester City (3-2 after the first leg) - 21:00 CET
This was always going to be the stand-out tie of the Champions League play-off round, and the two sides didn't disappoint, playing out a 3-2 thriller at the Etihad Stadium last week.
Jude Bellingham scored in stoppage time to give Los Blancos the advantage as the game heads to the Spanish capital, but it is a slender lead that could be easily overturned - especially with City's firepower.
Omar Marmoush showed why he will be a threat on the weekend, netting a first-half hat-trick against Newcastle United to see his side win 4-0 at home.
This is possibly the most confident City have looked in months, and they seem to be clicking at the right time for a tilt at Real.
For the Madrid side, they were held to a draw against Osasuna as Bellingham was sent off for dissent.
Of course, league form is not the be-all or end-all for this tie and with both defences looking shaky in the first leg, goals should be expected once again.
This tie is on a knife's edge and with the added jeopardy that one of the two previous winners of the competition will fall, it will be a thrill ride from start to finish.
Thursday, February 20th
Galatasaray vs AZ Alkmaar (1-4 after the first leg) - 18:45 CET
Despite being the dominant force in Turkish football right now, Galatasaray were flogged at AZ last week, conceding the most goals on anyone in the Europa League play-off first-leg ties.
That leaves them with a mountain to climb heading back to Istanbul, knowing they need at least three goals to force extra time. Only once in 57 attempts has a club managed to do that in this competition.
Despite this, optimism can be found in their abundance of talent up front. Victor Osimhen, Alvaro Morata as well as Dries Mertens are all proven goalscorers at this level and their attacking prowess has already been shown this year in the Europa League, scoring three times in each of their last five home games in the competition.
Their defence is shaky though, the biggest example of that coming a week ago, but with a partisan home support and an early goal or two, this could be a comeback for the ages.
Panathinaikos vs Vikingur Reykjavik (1-2 after the first leg) - 21:00 CET
Our final game comes from the UEFA Conference League, where more history for Vikingur Reykjavik could be made from 21:00 CET.
The Icelandic side have made it to the knockouts of a UEFA competition for the first time this season, and they could become the first side from the land of ice to win a knockout encounter ever if they overcome Panathinaikos.
They made a great start last week, winning the first leg 2-1, and it could have been much better had Fotis Ioannidis not slotted home a 91st-minute penalty to give the Greek side a lifeline.
Now, Vikingur face a trip to the fiery atmosphere of the Olympic Stadium in Athens, which will undoubtedly be a hostile environment for them. But, if they can chart a course through the match, history awaits them. Expect a tense and tight affair, with Panathinaikos having the lion's share of possession and xG, but make sure to keep an eye on what will be a fairy-tale if the Icelandic side can hold on.
