Middlesbrough defender Rav van den Berg has signed a five-year deal with German club Cologne.
Van den Berg leaves the Riverside for a fee believed to be £11.2m (€13 million), having played 66 games in two seasons after joining from Dutch club PEC Zwolle.
The 21-year-old Dutchman won Boro's player of the year award in the 2023-24 season and played in the Under-21 European Championships this summer.
But Van den Berg has not featured in either of the club's two games so far this season under new head coach Rob Edwards.
He now swaps the Championship for the Bundesliga with the newly promoted club.