Manchester City manager insists Italy are 'always stronger' with Balotelli leading the line.
Euro 2012: Italy must start with Balotelli against England, says Mancini
"Mario should always play," Mancini said to Gazzetta dello Sport. "He is the best and, with him, the national team is much stronger."
Prandelli did not start with the 21-year-old Balotelli for the first time at the European Championship in Monday's 2-0 triumph over the Republic of Ireland.
The temperamental forward came off the bench and scored his first goal in the tournament.
"Italy are much stronger if Balotelli plays," Mancini said. "If you look at the other day, he (Balotelli) came on, made an impact in the game and scored a splendid goal.
"I don't want to steal Prandelli's job because he is doing very well, but I consider Mario the best Italian striker.
"Mario is a champion and champions help you to win things.
"(Antonio) Cassano is a second striker and Di Natale is good but has different characteristics with respect to Balotelli."
Mancini, who led City to their first Barclays Premier League title since 1968 this season, expects a very difficult game on Sunday.
"England have to thank (former national coach) Fabio Capello," he said. "I don't want to defend him but that is the simple truth.
"You can see the work of a good and experienced coach like Capello is in this team.
"England are a well organised side who know what they want.
"(England manager) Roy Hodgson is an Italian Englishman.
"He is intelligent, good and crafty - the right man to continue Capello's work.
"England wait for their opponents and hit them on the counter-attack.
"This is the kind of football that we, Italians, were masters at for a long time.
"They have understood that winning is what matters at tournaments and Hodgson has always been a pragmatic coach.
"Italy will have to be aware of them on the break, but also make the most of their own characteristics - technique, speed and possession.
"It would be an error to take on England with force and aerial play."
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