Schalke welcome Nice to the Veltins Arena knowing that their spot in the next round is secure, while Mainz fight for their lives in Saint Etienne in need of all three points to keep their hopes alive.
Mainz travel to France on Thursday evening to face St Etienne, knowing that anything less than all three points could spell the end of this season's campaign in the Europa League.
Martin Schmidt's side currently sit third in Group C on five points with St Etienne and Anderlecht both on eight. A win on Thursday would see the Bundesliga side go level with their French opponents ahead of the final match.
"We have learnt our lessons from the Anderlecht game,” said Schmidt in Wednesday's press conference, referencing a bitter 6-1 defeat to the Belgian side in the previous matchday. "Tomorrow is a must-win game for us."
The German club have seen their form come undone of late, with just one win from their last six games in all competitions ahead of the international break. A 4-2 victory over Freiburg on Saturday would have went a long way to reviving some lost confidence, but a 1-1 draw in the previously clash at the Opel Arena suggests St Etienne go in to the match as favorites.
Christophe Galtier's side have lost just one of their last seven games and just one home match in all competitions this season. Should they avoid defeat on Thursday they'll confirm their spot in the next round of the European competition.
Schalke hoping to guard against complacency
Meanwhile Schalke will be enjoying themselves when they welcome their own French opponents, Nice, to Gelsenrkirchen on Thursday night.
Markus Weinzierl's side have already qualified for the next round after winning each of their last four games in the Europa League – including a 1-0 win over Nice in southern France on the opening matchday.
Led by former Borussia Mönchengladbach coach Lucien Favre, the Ligue 1side will be intent on picking up points while the hosts look to shake up their starting squad and rest more senior players.
Although Weinzierl admitted that he plans to "rotate the squad a little" he remains confident that his reserve players can step up to the challenge.
"We will put a team on the pitch who can and want to win the game at all costs,” he said. "There will be over 50,000 Schalke fans in the stadium and we are desperate to win for them. We want to extend our run."