FC Porto was fined ?20,000 ($26,650) on Tuesday after its fans aimed racist abuse at Manchester City players during a Europa League match.
City complained to UEFA after Mario Balotelli and Yaya Toure, who are both black, reported hearing abusive chants during their team's 2-1 victory in Portugal in February.
UEFA rules prohibit discrimination ''on grounds of color, race, religion or ethnic origin'' and Porto was found guilty of ''racist conduct of their supporters.''
Porto had suggested that the English club's players and officials misheard chants directed at its Argentine forward, Sergio Aguero.
''We welcome the UEFA sanction applied to Porto FC,'' said Piara Powar, executive director of FARE, European football's anti-racism body. ''It is the right action given the clear evidence of racial abuse during this game. The fine represents a first offense sanction according to UEFA's 'three strikes and out' principle. Further offenses will result in an increased fine and then a ban.''
Porto has the right to appeal.
After a 2-1 victory in Portugal, City also won the return match 4-0 to advance before being eliminated in the last 16.
