Besiktas and Fenerbahce have had their bans from next year's European football competitions upheld by UEFA.
The Super Lig duo were implicated in a match-fixing scandal relating to the 2010-11 season, which saw Fener secure the league title, before they were found guilty of match-fixing in June of this year.
Initially, Fenerbahce were given a three-year ban from European competition, while their Istanbul rivals were disqualified from this season's UEFA Europa League.
Besiktas' punishment has been upheld, however, Fener's punishment has been lowered slightly to a two-year ban.
A UEFA statement read: "The UEFA appeals body carefully analysed the statements and documents submitted by Besiktas and Fenerbahce related to their specific cases, as well as the statements and documents submitted by the UEFA disciplinary inspectors appointed to each case.
"Both clubs have the opportunity to appeal the decisions of the UEFA appeals body to the Court of Arbitration for Sport (CAS)."