Last year's Europa Conference League winners will take on their German counterparts twice in seven days, with the winner progressing to the final, held in Budapest later this month.
Match preview
While they may have slipped down a tier or two from their peak earlier this century, Roma are still major players on the European scene, as they reached a UEFA semi-final for the third successive season by beating Feyenoord in their quarter-final clash.
The Italian heavyweights were knocked out by Manchester United in the Europa League semis in 2021, while they defeated Leicester City at the same stage of the Conference League last term on their way to lifting the trophy - once again, Feyenoord were their victims in the final.
In fact, partly owing to the nous and know-how of coach Jose Mourinho, Roma have now progressed from 10 of their last 11 European knockout ties - including each of the last seven in a row.
In addition to seeing off the Eredivisie leaders, the Giallorossi have also overcome RB Salzburg and Real Sociedad to make the Europa League's final four, having finished runners-up to Group C rivals Real Betis during the autumn.
However, Mourinho's men have more recently gone four games without a win in Serie A, and following a 2-0 home defeat to Inter last weekend they are now five points off the all-important fourth spot with just four rounds remaining.
Their worst form of 2023 has come at a time when the Rome club's squad has been decimated by a series of injuries, leaving Mourinho lamenting his luck and grumbling about the paucity of resources at his disposal.
The Portuguese coach may even pack his bags for new surroundings this summer, if the rumour mill is to be believed, but he would love nothing more than to depart by securing more silverware. To do so, he must first overcome one of his most favoured students.
Bayer Leverkusen head coach Xabi Alonso was managed by Mourinho for three seasons at Real Madrid between 2010 and 2013, with only Cristiano Ronaldo playing more minutes for Los Blancos during that time.
The former midfielder has since worked his way through Madrid's coaching setup and was then chosen to turn Leverkusen's ailing fortunes around earlier this season - and to good effect.
Earning admiring glances from other clubs across Europe, Alonso recently guided his team through a 14-game unbeaten run in all competitions - featuring a total of 10 wins - though that streak finally came to its end last Friday, with a 2-1 reverse to Koln in the Bundesliga.
As a result, they sit sixth in the standings and are not assured of a return to continental competition for next season, but ahead of their trip to the Eternal City this week, Leverkusen remain nine without defeat away from home.
Eliminating Monaco, Ferencvaros and Belgian upstarts Union Saint-Gilloise to reach the Europa League semi-finals - following their failure in the Champions League group stages - Die Werkself have made this stage of a UEFA tournament for the fourth time, and the first since going on to lose in the 2002 Champions League final.
At that time, the Rhine club were cruelly dubbed 'Neverkusen' due to their narrow misses in league and cup competitions, but under their ambitious new boss, belief has grown that they can find a way past Roma - who have lost just one of their last 25 European matches at Stadio Olimpico - and go on to taste glory in the final.
Roma Europa League form:
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Roma form (all competitions):
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Bayer Leverkusen Europa League form:
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Bayer Leverkusen form (all competitions):
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Team News
Following a damaging spell of absences through injury and ill discipline, Jose Mourinho should be able to include some integral cogs in his Roma machine on Thursday evening.
Experienced campaigners Georginio Wijnaldum and Paulo Dybala both returned to training this week, but Chris Smalling - and his deputy, Marash Kumbulla - are still absent.
After serving a Serie A suspension, Zeki Celik is also available again, but Nicola Zalewski is more likely to start on the right flank in any case.
Tammy Abraham is set to replace Andrea Belotti up front, and captain Lorenzo Pellegrini again runs the show in midfield. Despite missing a penalty in Rotterdam last month, the latter has been directly involved in eight Europa League goals so far this season - scoring and assisting four times each.
Meanwhile, Bayer Leverkusen's Florian Wirtz has played a part in more Europa League goals than any other player since the conclusion of the group stage (three goals; two assists) and has also created the most chances (18).
The 20-year-old stars in the visitors' front three, which also features France winger Moussa Diaby. Either Amine Adli or Adam Hlozek should join them.
Xabi Alonso - who will be without Andre Lunev, Patrik Schick and Charles Aranguiz for the trip to Rome due to injury - is set to name a similar side to that which was beaten by Koln last time out.
Roma possible starting lineup:
Patricio; Mancini, Cristante, Ibanez; Zalewski, Matic, Wijnaldum, Spinazzola; Pellegrini, Dybala; Abraham
Bayer Leverkusen possible starting lineup:
Hradecky; Kossounou, Tah, Hincapie; Frimpong, Andrich, Tapsoba, Bakker; Diaby, Adli, Wirtz