Every time there is a change of coach at a club, there will be changes in the team's performance, especially since Dortmund also lost key players after the departure of Marco Reus and Mats Hummels. Nuri Sahin has no experience in managing teams at a high level such as the Champions League, Dortmund could experience a decline in performance due to the tactics used by Nuri Sahin not being in line with Dortmund's style of play, which is used to Edin Terzic direction.
There will be additional work for Nuri Sahin to find players who will replace Reus and Hummels, apart from that he also has to ensure that Dortmund is able to provide competition in the race for the Bundesliga trophy. It is difficult to predict Dortmund performance next season after changing coaches and losing key players, but Nuri Sahin first season in charge of Dortmund was a bit burdensome because under the control of Edin Terzic his performance was not too disappointing. Even though they failed in the UCL final, this achievement was very difficult for Nuri Sahin to achieve, who still lacked experience in managing the team.
that's true, every time there is a change there will definitely be changes, and of course it takes time to adapt to be better than before, it's just that changes don't guarantee they will be better, especially with Nuri Sahim who is inexperienced, of course this allows Dortmund There will be a decline in performance, but of course Nuri Sahmin will do his best with the changes he will make. This is the importance of time to adapt, because Dortmund are already used to Edin Terzic's direction, of course they need time to get used to Nuri Sahim's new direction.
It is not easy to find a replacement for Reus and Hummels, especially since these two players are players who are Dortmund's mainstay players because they have good performance and help Dortmund, which essentially plays an important role, because for example, these two players leave and Edin Terzic still holds Dortmund. It looks like he will have difficulty finding a replacement, but we don't know what Nuri Sahim will be like. We can only wait and see how their performance will be better or whether it will decline so they can't compete well in the Bundesliga.