Turkish league winners Fenerbahce were on Wednesday banned from the Champions League due to an ongoing match-fixing probe which has ensnared the Istanbul club.
They will be replaced in the tournament by Trabzonspor, last season's Turkish league runners-up, following a meeting of UEFA's emergency panel.
Earlier on Wednesday, the Turkish football federation announced their sanction on Fenerbahce, just 24 hours before the draw for the group stage of the money-spinning tournament is held.
"Regarding the heavy disciplinary sanctions both Fenerbahce and the Turkish Football Federation (TFF), which means Turkey as a whole, might encounter, it is decided to ban Fenerbahce Sports Club from the UEFA Champions' League this season," the TFF said in a statement posted on its website.
The decision was made after a warning by UEFA that either Fenerbahce should withdraw from the competition or the TFF should ban the club to prevent UEFA starting its own disciplinary investigation, it said.
The TFF then decided to ban Fenerbahce after the club refused to "make an important decision like that in this very short time," it said.
In a statement posted on its website, the club said the federation asked them to make the decision in less than a day.
After naming Trabzonspor as Fenerbahce's replacement, the UEFA emergency panel also decided that the Turkish league runners-up would be replaced in the Europa League by their opponents in the play-off, Athletic Bilbao.
Their play-off second-leg match, scheduled for Thursday, was therefore cancelled.
UEFA general secretary Gianni Infantino said: "The panel considered that the Turkish Football Federation took the right decision to protect the game, fully in line with our zero-tolerance policy against match-fixing.
"The Turkish Football Federation has shown with this decision that it takes full responsibility in the fight against corruption."
Last month, some 30 people were charged and jailed pending trial as part of a probe into match-fixing and bribery in Turkey's first and second divisions.
The president of Fenerbahce, Aziz Yildirim, is the most prominent among a list of incarcerated suspects that also includes the vice-president and the coach of another Istanbul giant, Besiktas.
The suspects are accused of manipulating 19 games last season, in which Fenerbahce clinched the title on the final day, outstripping Trabzonspor on goal difference.
The inquiry and arrests have sent shockwaves through fans in football-mad Turkey, amid the prospect of Fenerbahce losing the title.