Manchester City manager Manuel Pellegrini has been charged with misconduct for his comments about the referee after his side's 2-0 Champions League home defeat by Barcelona, UEFA said on Friday.
Pellegrini questioned the impartiality of Swedish official Jonas Eriksson and accused him of deciding the outcome of Tuesday's last-16 first-leg match.
The Chilean has been charged with violating the general principles of conduct, European soccer's ruling body said in a statement.
The case will be handled next Friday.
Pellegrini had earlier apologised for his comments, but maintained Eriksson did play a role in the result.
"When you lose a game the way we lost against Barcelona, you are frustrated, you are angry," he told a news conference ahead of Saturday's Premier League home match against Stoke City.
"Maybe I said something but I don't think that way. I want to apologise for what I said.
"I felt from the beginning his criteria was not the same for both teams, I think he had a bad day - everyone can have a bad day - but I didn't say that intentionally he didn't give fouls for us or did give fouls for Barcelona."
City fell behind early in the second half when Eriksson awarded a penalty for a foul by Martin Demichelis on fellow Argentine Lionel Messi on the edge of the box and the defender was sent off.
There were suggestions a City player had been fouled before the incident.
The normally mild-mannered Pellegrini said in a post-match news conference: "The referee was not impartial. He did not have any control of the game. I think it was not a good idea to have a referee from Sweden in such an important match."
He also said the referee should not be in charge of Barcelona games as he was involved in a controversial match between the Spanish side and AC Milan in 2012.
"I repeat I didn't have any serious accusation, not against UEFA, not against the referee, not against Sweden, not against anyone so it was my way of thinking and I was angry," Pellegrini added on Friday.
"I am sure this is a good referee because UEFA are always evaluating all the referees and if he is not a good referee, he is not in the UEFA staff. The thing I said in that moment doesn't mean what I think."
Looking ahead to the visit of 14th-placed Stoke, Pellegrini said captain Vincent Kompany should be fit to play and that striker Sergio Aguero should return to full training on Tuesday.
Image: Manuel Pellegrini
Photograph: Clive Brunskill/Getty Images
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