United and Barca turned down Mario
The 19-year-old has netted 11 times in 35 Serie A outings since arriving from Lumezzane in 2007, but has been omitted by Nerazzurri chief Jose Mourinho on more than one occasion for displaying both a poor attitude and questionable temperament.
Balotelli has scored five times in 12 appearances for the Italian U21 side, but saw red in this summer's U21 European Championships in Sweden for retaliating against the hosts' Pontus Wernbloom.
However, the front-man was still strongly linked with a move to West Ham United during the summer transfer window, while Arsenal boss Arsene Wenger revealed that he is an admirer of the talented youngster, saying:
"I am keeping an eye out for Balotelli, a player I like very much. In my view he can be one of the best."
But, according to Spanish daily El Mundo Deportivo, Balotelli's future could have panned out much differently, with both of last season's Champions League finalists, Manchester United and Barcelona, believed to have been keen on recruiting the prodigy while he was still at Lumezzane, but balked at the price needed to secure his services.