Maybe, if in the group phase Bayer Leverkusen is not together with the top teams, then maybe Bayer Leverkusen will have a chance to become group winners or maybe just runners up. But the point is, I personally believe Bayer Leverkusen is capable of advancing to the knockout phase of the last 16, the quarter-finals or maybe even qualifying for the semifinals. Because I personally am still quite confident about the quality and abilities of Xabi Alonso, even though there may be several key players who might leave, but I still believe Xabi Alonso will be able to make the Bayer Leverkusen squad good next season. Therefore, failure to win the Europa League trophy and at the same time failing to win the treble winner last season will of course allow Bayer Leverkusen to improve better next season.
It depends on how they perform, if they are in a relatively easy group but they fail to perform well, I think that will also be a problem. We can see how Manchester United fared in the Champions League group stages this season. They were the favorite team to qualify for the group, but their performance was very disappointing and that meant they had to fail and they were even ranked last in the final standings.
Leverkusen is a team that is playing well this season, even though they are in a difficult group, but if they can perform well I still believe that they will be able to qualify from the group. Once again this depends on how they will look. Whether they will play well or not. This requires consistency, that is one of the important factors that every team must have. Xabi Alonso must have realized that their opponents were a good team too, so he had to prepare everything very well.
Well I don't why my thoughts are this way but I feel Bayern Leverkusen this season will be the center of eyes of all their opponent they are playing because in the football world now knows the capability of this team and will definitely not underated them and this was what Leverkusen also used to win lots of games as team didn't actually knew their capability and aslo game style but this time this case would be different and that's why they need to work hard @xabi Alonso.