Mancini said the 21-year-old, reported by local media to have played with his iPad while on the bench during Italy's Euro 2012 qualifier against the Faroe Islands last week, often had his behaviour blown out of proportion by the newspapers.
"I am disappointed because everything that Mario does is a big situation," the coach told a news conference.
"I think that Mario played well for Italy on Tuesday [against Slovenia], this is important, it is important that tomorrow he can play [against Wigan Athletic] - the other situation is not important."
Asked if Balotelli should moderate his behaviour, Mancini replied: "I hope. But Mario is 21-years-old, he can change in two months, three months or six months.
"I think that you are right, the moment he changes his mind, he changes everything."
The volatile Balotelli, who last year said he was second only to Barcelona's Lionel Messi in the talent stakes, picked up multiple red and yellow cards last season and a "bad boy" reputation off the field.
He angered Mancini in a pre-season match against the LA Galaxy when he attempted an audacious trick shot - involving a pirouette and a backheel - and was promptly substituted.
He has yet to start in the Premier League this season where City have got off to a perfect start with three wins from three games but Mancini's comments suggest he could get the nod for Saturday's match at home to Wigan.
Playmaker Samir Nasri should be available for the game despite a broken finger and defender Micah Richards has recovered from a tight hamstring. Nigel de Jong misses out with an ankle injury and fellow midfielder Gareth Barry is a doubt with a similar problem.
Two players who definitely will not feature are Owen Hargreaves and Kolo Toure, who are a fortnight away from fitness.
Hargreaves was a surprise addition to the City squad, joining from neighbours Manchester United as a free agent after four injury-plagued years with the English champions, but Mancini was confident he might soon revive his career.
"I think if Hargreaves will be fit in two weeks I think he can play always," the Italian said. "He is 30-years-old, he's young. He was very unlucky in the last two years... he trained with us this week, he worked last week, I think he needs another two weeks to work to find a good confidence."
Hargreaves has not been included in City's squad for the Champions League group stage, which gets underway on Wednesday at home to Napoli, but Toure, who is back from a six-month doping ban, has been.
"He's fit but he needs to play because it's one year that he has not played," Mancini said of Toure, whose last City game was in February. "I think that in two weeks he can play."
