I think Mourinho's quality has been declining for a long time, because before Mourinho coached AS Roma and the truth is Mourinho has failed to deliver good results at several clubs before. So, even though AS Roma is ready to buy some good players in the upcoming transfer market, but I personally don't believe Mourinho will be able to make AS Roma better and stronger.
But apart from that, of course, at this moment Mourinho just needs to focus on finishing the season well. Because after all, at this moment it is also a fact that Bayer Leverkusen is not a weak team because yes, Bayer Leverkusen has managed to improve so rapidly in the Bundesliga as well. Therefore, AS Roma does not have a big chance to qualify for the final, because of course Bayer Leverkusen will try their best to qualify for the final and this match will never be easy for both of them.
Mourinho is a very peculiar coach, discipline in the team is important to him and I noticed such a thing, if the players and listen to him, then the team shows the best results. On teams with a lot of star players, this didn't work because he had too many conflicts with players who didn't want to give in to his "quirks", like warming up in the parking lot before a match, when he was in Manchester United.
In my opinion, everything is not so bad in Roma, I mean the relationship with the players. And I think if Roma manages to finish the season in the top 4, then Mourinho will definitely get a good budget to strengthen the team, but to tell you the truth, I don’t believe that this is within the power of the current Roma.
Actually, Mourinho is the main reason many people think Roma is going to win this game otherwise Roma is not a strong team in a good situation to beat Leverkusen especially when we consider the recent performance of Leverkusen and how they won Bayern Munich this season, that's why we can even expect to see them winning the game against Roma easily.