|Yildirim is accompanied by plainclothes police after the allegations emerged last week [EPA]
An Istanbul court jailed the chairman of league champions Fenerbahce on Sunday pending trial on charges of match-fixing, TV reports said.
The investigation could result in the club being stripped of their title.
Chairman Aziz Yildirim joins 25 people already remanded in custody after police raids at the weekend, prompted by evidence of manipulation in 19 matches, which Turkey's prime minister said has stained Turkey's image.
Yildiz had been taken for medical treatment after prosecutors called for him to be jailed on Friday, but his questioning was completed on Sunday, and the court ordered him to be jailed.
According to media reports, Fenerbahce and Yildirim are at the centre of the investigation.
The suspects are accused of manipulating games last season which saw Fenerbahce clinch the title in the final game, outstripping Trabzonspor on goal difference.
Fenerbahce's vice-president Sekip Mosturoglu and financial chief Tamer Yelkovan are among the suspects already in prison.
Two Fenerbahce players – Nigerian striker Emmanuel Emenike and forward Sezer Ozturk – were questioned and released.
The Turkish Football Federation is expected to decide whether to slap any immediate sanctions on the Istanbul giants by Friday, the deadline to notify UEFA of which teams will play in European competitions.