The UEFA Europa League, the second-tier European club championship, is poised for some first-tier action as five-time continental kings Barcelona visits Napoli on Thursday.
Barca needed a Ferran Torres penalty to draw at home to Napoli in the first leg of its knockout round play-off tie after Piotr Zielinski put the Serie A side in front at the Camp Nou.
However, with the away goals rule having been dispensed with this season by UEFA, the heavyweight tie remains very much in the balance going to the Stadio Diego Armando Maradona.
Barcelona is enduring a troubled season, but Xavi Hernandez's side still crosses the Mediterranean in good form having gone five unbeaten and not lost in 90 minutes since Bayern Munich dumped it out of the Champions League in early December.
It won 4-1 at Valencia in La Liga at the weekend with Pierre-Emerick Aubameyang scoring a hat trick, while Napoli is third in Serie A after drawing 1-1 with Cagliari on Monday.
Barcelona is one of four Spanish teams aiming to advance to the last 16, with Real Sociedad hosting RB Leipzig and Real Betis leading 3-2 against Zenit St. Petersburg after the first leg in Russia.
Sevilla, the record six-time winner of the second-tier European competition and who will host this season's final, leads 3-1 as it goes to Dinamo Zagreb.
Elsewhere, Scottish champions Rangers are hoping to secure a spot in the last 16 as they welcome Dortmund to Ibrox following their stunning 4-2 win in Germany.
It would go down as one of the best results in their history in Europe if they could see off the Bundesliga giant, who will be once again without star striker Erling Haaland.
The Norwegian, scorer of 23 goals in 20 appearances for his club this season, missed the first leg and his team's last three domestic outings due to injury.
U.S. starlet Gio Reyna, whose father Claudio played for Rangers and is a close friend of the Ibrox side's manager Giovanni van Bronckhorst, is also sidelined.
The squad announced for the trip to Glasgow, however, included right back Thomas Meunier, with the Belgian returning from a knock.
Dortmund's poor first-leg showing last week shocked fans but it did smash Borussia Monchengladbach 6-0 in the Bundesliga at the weekend.
In the Europa Conference League, Marseille, PSV Eindhoven and Leicester City are among the teams primed to advance to the last 16 but Celtic must overturn a 3-1 first-leg deficit as it travels to Norway to play Bodo/Glimt.
The Norwegian champion shocked the Scottish Premiership leader at Parkhead but Celtic captain Callum McGregor believes it can turn the tie around in the Arctic Circle.
"We are that type of team that still want to be aggressive even if we are going away from home, we still want to play the same way, and that way will get us chances," he said.
"It's then just being ruthless and clinical when the chances come."
Turkish heavyweight Fenerbahçe will look to overturn the odds as it visits Slavia Prague in the return leg of its UEFA Europa Conference League last 16 playoffs.
The first leg between the two teams in Istanbul ended in a 3-2 defeat for the Turkish side.
Fenerbahçe will need to win by at least two goals to confirm its place in the last 16 of the European third-tier tournament.
But it will have to do so without injured Luiz Gustavo and Filip Novak. Midfielder Miha Zajc will also miss the match through suspension.
However, midfielder Irfan Can Kahveci and defender Kim Min-jae could return to action after recovering from injury.
The match at the Czech capital will kick off at 9 p.m. local time (8 p.m. GMT).