Mario Balotelli bib blunder
Balotelli was already seen as an enfant terrible at Inter Milan before Mancini managed to sign him for Manchester City last summer in a deal worth a reputed £23 million. And a series of injury setbacks, disciplinary problems and off-field indiscretions have not done anything to change that perception.
The striker was singled out for criticism by Mancini after Thursday night's Europa League exit to Dynamo Kiev, with Balotelli missing a gilt-edged chance before being sent off for a high tackle on Goran Popov. It was the 20-year-old's second red card of the season, to add to the eight yellows he has also been shown.
Balotelli escaped being dropped for Sunday's game at Chelsea by publically apologising for that sending off, but Mancini says his antics must stop.
And the News of the World claimed on Sunday that Mancini was so incensed after the Dynamo match that he picked up a suitcase in the dressing room and threw it at the striker, shouting: "I don't want to see your face again."
Asked if his reputation was being harmed, Mancini told the Sunday Mirror: "Yes, this is true. I trusted him 100% but after this latest incident it's very difficult to trust him. If he continues like this it is very difficult. I think it's time for him to stop losing control. I don't like this.
"I think that he's a young player but it's time he started to think with his head. Time to use his brain because if not it is very difficult. He's a fantastic player but I don't deserve this situation and neither does the club or the rest of the squad.
"Balotelli is not repaying my trust at the moment. He should work more to repay me. I work every day with him. And I hope that every day he can improve like a player, improve like a man.
"Our big players are not important just because they play well. They are important because they have to help their team-mates when we have a difficult game. Every day I speak with him. I know him very well. I know that he can become a strong player, one of the best players in Europe.
"He is very lucky because he plays football. When you play football it is a fantastic sport. You can play and enjoy every game, every training session. It's not difficult. I would like him to understand better about his behaviour."
Meanwhile, Man City were on Sunday linked with a £24 million move for Chile winger Alexis Sanchez, who plays for Udinese.