Union Berlin have reportedly struck an agreement with Turkish giants Galatasaray to sign Ghanaian defender Derrick Köhn in a deal worth around €5 million.

Köhn, who spent last season on loan at Werder Bremen, impressed with 27 appearances and two goals in the Bundesliga. Despite returning to Galatasaray hopeful of cementing a first-team place, competition in the squad forced him to seek opportunities elsewhere.

Werder Bremen had shown strong interest in signing the 25-year-old permanently, but negotiations with Galatasaray fell through. Union Berlin have now moved quickly in the last 48 hours to finalize terms and secure his services.

The deal is also expected to include a sell-on clause, ensuring Galatasaray profit from any future transfer involving the Ghanaian left-back.

For Köhn, the move represents a fresh chance to establish himself as a key figure in the Bundesliga, while Union Berlin strengthen their defensive options ahead of the new campaign.