Nothing is impossible in football, Leverkusen is quite strong and consistent up to now, but Stuttgart is not an easy opponent for them because Stuttgart this season has improved a lot compared to last season, although I admit that if you look at it overall, Leverkusen is superior, but Stuttgart who will play in front of his own supporters cannot be underestimated.
So far, Xabi Alonso has built a very strong Leverkusen team on all fronts, but with this season still having a very long way to go, their consistency is still being questioned because so far the Leverkusen main team has had very little player rotation so I think Xabi Alonso only relies on his main players and It's a bit risky if injuries or other undesirable things happen to the main squad.
Discipline and good road map for the developments of a club will elevate them to greater heights in football and in major tournaments. Consistency and appropriate signings is basically what a club needs to get back on winning track, nothing more is needed. Applicable to Bayer Leverkusen whereas they have a competitive squad and a promising young coach, Xabi Alonso. He has visions and solid plans for the club, he has achieved quite reasonable amounts and won't fall victim to defeats this moment, as he aims to win the Bundesliga title.