Leverkusen this season has made history by winning the Bundesliga title for the first time in the club's 120-year history, the history is even more impressive after they were able to achieve it with a record of 0 defeats in the league, next season of course Leverkusen will try to continue their positive trend by playing in the Champions League, so indeed Alonso needs careful preparation to be able to repeat and also maintain their performance next season both in the Bundesliga and Champions League, looking at the list of teams that will play in the Champions League next season, of course Leverkusen should start trying to improve their current squad.
Alonso is one of the smart coaches who is able to make a lot of changes to Leverkusen, so indeed the fans and management of course have high expectations for Alonso to be able to bring glory in the Champions League next season, but I think the management should also try to keep each of their star players so that they are not taken by other teams, so far it is reported that Leverkusen has lost some of their players who have indeed been recruited by other teams, So it will likely be difficult for Alonso to maintain Leverkusen form next season if they continue to lose their players.
Leverkusen will not be as good next season as they were this season, I just believe that. Do I have any clue or data why? Absolutely not, they could be even better and this time not lose a single game and win the treble, we have no proof that they won't.
But, do we really believe that they will go unbeaten on all games at bundesliga again, and win the cup again without a loss, and then beat everyone at UCL? Of course not, I mean we just "know" that it won't happen, so we are accepting the way it is. That is why I think it should be noted that we are going to end up with something that will take a while for us to see but something we already know anyway. I feel like it is a very simple situation to be in without a doubt.