Fenerbahce president Aziz Yildirim has been remanded in custody and charged as part of the criminal investigation into Turkish match-fixing.
Yildirim and 25 others, including directors of 2010/11 Super Lig champions Fenerbahce, as well as players, are set to face trial over alleged match-fixing.
The president was one of 61 people arrested as part of the investigation, following raids across the country on July 3.
Yildirim had been allowed to receive treatment in hospital last week, but he was sent back to jail after police finished questioning him on Saturday.
Fans of the Istanbul club, who narrowly beat Trabzonspor to the title last season, protested in support of Yildirim.
Fenerbahce released a statement on Saturday defending the senior figures implicated in the scandal.
"We do not believe the accusations that have been made against the president and directors,'' the statement said.
UEFA are due to receive confirmation from the Turkish FA by Friday confirming which clubs will take part in the forthcoming Champions League campaign.
Fenerbahce could be stripped of last season's title and even relegated when punishment is handed down, while individuals found guilty face heavy fines and prison sentences.