Kick It Out said it was 'sickened by the disgusting racist abuse' and suggested UEFA should have taken stronger action.
However, one goal proved enough for City who picked up their sixth successive league win to move four points clear of Liverpool, who host Aston Villa later on Saturday, at the top of the standings.
A round-up of Saturday's action in the Premier League.
IMAGES from the English Premier League matches played on Tuesday
IMAGES from Premier League matches played on Saturday.
Images from the English Premier League matches played on Wednesday.
Arsenal are eighth, seven points adrift of fourth-placed Chelsea, while Norwich remain second from bottom.
Images from the English Premier League matches on Saturday.
Manchester United manager Ole Gunnar Solskjaer is eager to build his team around midfielder Paul Pogba despite media speculation linking the French World Cup winner with a move away from Old Trafford.
Images and summary of all the World Cup 2022 qualifiers played across continents on Tuesday.
News of all that's transpired on and off the football field