Cologne officially announced on Wednesday that Dutch defender Raf van den Berg has joined from Middlesbrough on a five-year contract that runs until June 30, 2030.

The 21-year-old Raf van den Bergh came from Zwolle's youth training and made his debut for the first team in the Eredivisie on May 1, 2021. He has played for Middlesbrough since July 2023 and has made 66 appearances so far, contributing 1 goal.

According to various media reports, Van den Berg's base transfer fee is €8 million, which could reach up to €10 million after including variable bonuses. He will wear the number 33 jersey at Cologne.

Regarding Van den Berg's arrival, Cologne's sporting director Thomas Kessler commented: "We had already included Rafe on our transfer list and are very pleased that he has chosen to join Cologne. We are convinced that his quality will be of great benefit to us."

"Despite his young age, Ruff has already gained a wealth of experience in the Championship. He is strong and athletic, adept at both defensive tackles and playmaking from the back. With his qualities, he will bring greater stability and flexibility to our defence."

Van den Berg said: "I'm really looking forward to taking the next big step in my career and playing for FC Köln. Thomas Kessler played a major role in my decision to join Cologne. From the very beginning, he made me feel that the club really wanted me to play for them. I believe that the Cologne family is a great environment for me. It may sound cliché, but I really need this kind of atmosphere. I can't wait to make my debut in front of the Cologne fans and give my all for them."