[2] In the same year, he joined the youth academy of Hamburger SV and was an assistant coach there.
[1] When Daniel Thioune was appointed head coach of the first team of VfL Osnabrück in the 3.
[4] Before the end of the 2020–21 season Thioune was sacked, but Polzin remained in the coaching staff at the club and was also the assistant of the new manager Tim Walter.
[5] Tim Walter was sacked in February 2024 and Polzin was inserted as caretaker in the 2–2 draw against Hansa Rostock.
[8] On 22 December 2024, after a 5–0 victory over Greuther Fürth on the previous day, he was promoted to main manager of the club, after reaching eight points out of four matches played.