Balotelli was involved in a car accident earlier this week.
Allegri said: "I judge Balotelli based on what he does on the pitch. He didn't do well on Sunday against Parma and I took him off. He'll be available tomorrow and I think he'll play well. He trained well yesterday and I think he should be left in peace as well.
"There's far too much discussion of the man's private life. I think that Balotelli should be judged for what he does on the pitch like all other players. They're football players and should be judged as such. Balotelli arrived at the club in January and has done great things with the team since his arrival. He got 12 goals in his first 13 games.
"He played well at the start of this season as well. It can happen that a player has a dip in form, but when it happens to Balotelli, it's blown out of all proportion."
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