Giampaolo Pazzini will be sidelined for at least four months after the Milan man underwent knee surgery.
The summer signing from Inter has been struggling with right knee issues this season and a decision to operate was taken.
The Italian international, 15 goals in 30 League games for the Diavolo, had the procedure carried out in Belgium by Professor Martens.
Milan have confirmed that the 28-year-old will be out of action for between four and six months if there are no complications.
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