Footage has circulated on social media that captured the moment Xabi Alonso found out who his side will face in the Europa League semi-final.
In his first full season in charge at the BayArena, Alonso has enjoyed unprecedented success at the club, leading them to their first ever Bundesliga title with a thrashing of Werder Bremen last weekend.
Alongside their domestic heroics, Leverkusen remain in the hunt for their first European honour in more than three decades.
After comfortably defeating West Ham last week, Alonso's moved into the final four of the Europa League with a 1-1 draw on Thursday.
As Jeremie Frimpong netted a late goal at the London Stadium to secure Leverkusen's place, AC Milan and Roma were battling it out to join them in the semi-finals.
Roma took a two-goal lead at the Stadio Olimpico to increase their aggregate advantage but shortly after found themselves forced onto the back foot following Zeki Celik's first-half dismissal.
While Milan were able to find a late goal through Matteo Gabbia, the hosts ultimately held firm to continue their remarkable turnaround since Daniele De Rossi succeeded Jose Mourinho in January.
In the clip shared online, Alonso and his colleagues appeared to rejoice at the prospect of facing Roma in next month's semis.
Fans online however warned that the confidence could prove to be misplaced when the two teams clash over two legs.
One wrote: 'If they underestimate Roma, they will find out the hard way.'
Another asked: 'Why the jubilation? They must have confused this Roma with Jose Mourinho's Roma.'
A third fan added: 'Underestimating almighty Roma might get u thundered In the semifinal'
One reason for the seemingly exultant reaction to facing Roma could be that it offers the club a chance to exact their revenge of the Giallorossi.
The two teams met in the semi-finals of last season's competition, with Roma narrowly emerging victorious 1-0 on aggregate before being defeated by Sevilla on penalties in the final.