City have been reported to Uefa after jeering during the competition’s traditional pre-match ceremony in a protest against the European governing body prior to last month’s home clash against Sevilla.
The club could face disciplinary action but Pellegrini would have no issue if there was a repeat prior to tonight’s return Group D match at Ramon Sanchez Pizjuan Stadium.
Pellegrini said: “Everyone has the right to boo and protest. It is important how they do it, but, if they think something is wrong, I think everyone has the right to say what they want.
“It is very difficult for me to analyse why they boo and the way they do it, but my general opinion is if they boo, Uefa are not doing something right.”
City’s fans have had numerous issues with Uefa in recent years, but ill feeling increased a year ago when a game in Moscow was ordered to be played behind closed doors.
That was as a punishment for numerous offences by CSKA fans – including racial abuse – but City fans were also banned from the ground, with no allowance made for those that had already arranged travel, visas and accommodation.
City will secure their place in the last 16 if they win tonight and Juventus win at Borussia Mönchengladbach, but they know that Europa League winners Sevilla are no pushovers.
Pellegrini said: “They have a stadium with a fantastic atmosphere. They have got some fantastic players and we know we are up against a team that plays very well.”
“Of course it is a benefit if you qualify as soon as you can and it is not easy to do it three or four games before. But in the same way, if you are qualified, you must then try to fight for the first position of the group. So, this is not a game that will finish the group stage.”