The stakes could not be higher with the second-leg fixtures set to decide the quarter-finalists. Some teams hold significant advantages, while others must fight to overturn first-leg deficits. Here is a look at what to expect from each fixture.
Each second-leg fixture promises to be a high-stakes battle, with teams looking to either build on their first-leg advantage or mount a comeback to secure a place in the quarter-finals.
Barcelona took a slender 1-0 lead to the Olimpic Lluis Companys Stadium after a hard-fought first-leg victory in Lisbon. However, they will be without young defender Pau Cubarsi, who received a red card in the first leg.
Benfica, still very much in the tie, will be aiming to take advantage of any defensive gaps and stage a comeback in search of a quarter-final spot. With a potential clash against Borussia Dortmund or Lille awaiting the winner, both teams will leave everything on the pitch
Inter Milan host Feyenoord at the San Siro with a commanding 2-0 lead from the first leg in Rotterdam. Simone Inzaghi's side put in a disciplined performance despite their injury concerns in the full-back positions, and they will now look to finish the job on home soil.
Feyenoord, on the other hand, must produce a remarkable turnaround if they are to upset the Italian giants.
Bayern Munich take a comfortable 3-0 advantage into their second-leg clash with Bayer Leverkusen after a dominant performance in the first leg. Kompany's men were clinical in front of goal, while Leverkusen's evening was made worse by Mukiele's red card, leaving them shorthanded for this decisive fixture.
Xabi Alonso's side faces a near-impossible task against a Bayern team that rarely lets such an advantage slip.
Liverpool return to Anfield with a narrow but crucial 1-0 lead over PSG, having edged the first leg in Paris. The Reds, in exceptional form under manager Arne Slot, will look to capitalise on their home advantage to secure progression.
PSG, meanwhile, must find a way to break down a resilient Liverpool side while keeping their own defence tight to avoid elimination at this stage.