Mancini is not convinced the controversial striker has changed and wants too see evidence of a better attitude on the pitch.
He said: "Mario is the same. Maybe he can improve but I don't think he will change in one month.
"If he always plays like he did in the European Championships then yes, he will get better.
"But he has a big responsibility here, for us. He is an important player who we spent a lot of money on. He can do his job better here."