Kay Seidemann switched sides from Rot-Weiß Erfurt to Carl Zeiss Jena. During his first appearance in Rothenstein, there was a scuffle with the fans who wanted to confront him. The chairman of Carl Zeiss Jena stated that the decision to proceed with the transfer was supported by the club, despite some fans' objections due to Seidemann's previous negative remarks about the club.

Carl Zeiss Jena has signed Kay Seidemann from their arch-rival Rot-Weiß Erfurt. He has arrived at the training camp under special protection.