Centre back Cenk Özkacar is returning to Spanish parent club Valencia as Bundesliga side Cologne said they will make use of an option to make the signing permanent.
Cologne made the decision although Turkey's Özkacar played in 27 of their 34 top flight games and started in 21 of them.
“The departure is one that really hurts. He is a great character that, even when we told him of our decision, he wished us all the best for the future. He is a very positive person and that was seen in the dressing room," managing director Thomas Kessler said.
"Despite that, we decided not to make use of the option to buy because we are looking for a different profile at centre-back."
Cologne finished 14th, three points above the danger zone, in the past season.
