The team, which finished as runners-up in the tournament last season, has now suffered four consecutive losses across all competitions. Currently, Dortmund is positioned 10th in the Bundesliga, trailing leaders Bayern Munich by 20 points.
Reports from German media suggest that potential candidates to replace Sahin include former Manchester United manager Erik Ten Hag, who has been spotted at recent Dortmund matches, and ex-Benfica and Bayer Leverkusen coach Roger Schmidt.
Sahin, who served as an assistant to Edin Terzic during last season's unexpected Champions League final run, was elevated to the head coach role over the summer.
“We have unfortunately lost faith that we will achieve our sporting goals,” sporting CEO Lars Ricken said on Wednesday.
Ricken added the decision “hurts… but was unavoidable after the game in Bologna.
“We value Nuri Sahin and his work very much, we hoped for a long collaboration and until the end we had hope that we could achieve a sporting turnaround together.”
The dismissal marks a challenging period for recent managers at Dortmund. Since Jurgen Klopp's exit in 2015, the club has seen eight head coaches, including two terms for Edin Terzic. Only Lucien Favre has managed to remain for more than two years.
On Wednesday, Dortmund announced that U19 coach Mike Tullberg would step in as interim manager, starting with the home match against Werder Bremen on Saturday.
A disheartened Nuri Sahin expressed that he “unfortunately could not meet Dortmund’s sporting ambitions at this time,” adding, “I wish this special club all the best.”
Sahin’s appointment continued the club's trend of placing former players in key leadership roles. Terzic, who grew up in the area, previously served as a scout and youth coach before assuming the head coach position. Both Matthias Sammer and sporting director Sebastian Kehl also enjoyed lengthy careers as players for Dortmund.
Sahin, who progressed through Dortmund’s youth system, played 274 matches for the club and was part of the team that secured the Bundesliga title in 2011, alongside his spells at Real Madrid and Liverpool. His first head coaching role was with Turkish club Antalyaspor, where he concluded his playing career.
At Antalyaspor, Sahin led the team to seventh and thirteenth place finishes in the league before returning to Dortmund as an assistant manager in January 2023. Following Tuesday's defeat, he remarked to reporters, “if I am the problem, or if a change of coach solves the issues, then that’s no problem at all.”
This season, under Sahin's leadership, Dortmund has struggled significantly away from their 82,000-seat Westfalenstadion, recording nine losses and only four wins in 15 matches.
In addition to their disappointing league performance, Sahin's team was knocked out of the German Cup in the last 32 by Wolfsburg.
However, they still hold aspirations of advancing to the Champions League knockout stage, despite a recent loss to Bologna, as they currently sit in 13th place in the league.