A youth product of SC Marklohe,
Werder Bremen and
Borussia Dortmund, Osterhage began his senior career with the
reserves of Borussia Dortmund in 2020. On 7 June 2021, he transferred to
VfL Bochum. He made his professional debut with Bochum in a 3–0
Bundesliga loss to
RB Leipzig on 2 October 2021, coming on as a late sub in the 82nd minute. On 15 April 2024,
SC Freiburg announced the signing of Osterhage from summer 2024. ==International career==