Leon Klassen

Klassen made his professional debut in the 3. Liga for 1860 Munich on 31 July 2019, coming on as a substitute in the 87th minute for Benjamin Kindsvater against FSV Zwickau. He assisted Herbert Paul for Munich's third goal, with the match finishing as a 3–0 home win. On 27 May 2021, he signed with WSG Tirol in Austria. On 30 December 2021, he signed a 3.5-year contract with Russian Premier League club FC Spartak Moscow. Klassen left Spartak by mutual consent on 27 June 2024. On 29 August 2024, Klassen signed a two-year contract with Lyngby in Denmark. Klassen joined SV Darmstadt on 21 June 2025. On 20 January 2026, he was loaned by Grazer AK in Austria. On 9 July 2026, Klassen returned to Grazer AK on a permanent basis and signed a three-year contract with the club.

Klassen was born in Germany to a Russian parents; his mother is of German descent. He is a youth international for Russia.

As of match played 25 May 2024

TSV 1860 Munich Regionalliga Bayern: 2017–18 Bavarian Cup: 2020 Spartak Moscow Russian Cup: 2021–22