
The background to the ban is a dispute between Hakan Calhanoglu and the Turkish club Trabzonspor. During his time at Karlsruhe SC in 2011 Calhanoglu, as a minor, reached agreement with Trabzonspor regarding a transfer. However, he extended his contract at Karlsruhe SC and later joined Hamburg SV. The CAS agreed with FIFA that the actions of the player represented a breach of contract with Trabzonspor.
Bayer 04 Leverkusen were not involved in the proceedings as the player signed for the Bayer 04 Leverkusen several years after the incident. "Of course, we regret this decision which is completely incomprehensible for us," said sporting director Rudi Völler. "It's a heavy blow for Hakan but also for us. We’re also being heavily punished although Bayer 04 Leverkusen had nothing to do with the events in 2011. We are now missing a very important player in a crucial phase of the season."
Bayer 04 CEO Michael Schade also criticised the verdict. "In addition to the player, it also affects the club that played absolutely no part in the events of the time. Unfortunately we are left with no alternative but to accept the decision," said Schade.


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