Tuttomercatoweb report Balotelli was whistled during the club's latest match, a 1-1 draw at home to Lazio on Sunday evening.
Balotelli came off the bench for the final 16 minutes of the fixture, and had little impact, attempting two shots which landed off target.
He has scored just one league goal all season for Milan, the campaign just as unproductive as his spell at Liverpool last season.
A return to the club which sold him was hoped to get him back to his best, but the 25-year-old is struggling badly and has lost his place in the Italian national side.
Now with fans on his back too, the chances of him signing for AC Milan on a permanent basis will become even more tricky.
From Liverpool's perspective that would be a blow, and they will have to hope Balotelli's profile allows him to find a club willing to give him a fresh start, but may be reliant on the striker being willing to accept a reduction in wages to do so.