Stephan El Shaarawy has suffered a thigh strain, so will miss out on Torino-Milan and Celtic next week.
The Italy international had been named in Milan’s squad for the Toro game, which kicks off on Saturday at 19.45 UK time.
However, he picked up a muscular problem in the final training session on Friday and the club released a statement.
El Shaarawy has suffered a muscular lesion on the femoral bicep of the right thigh.
“Over the next few days the player will undergo further tests to stabilise a prognosis and recovery time.”
It is another heavy blow for the Rossoneri, who are already missing Daniele Bonera, Giampaolo Pazzini, Matias Silvestre, Mattia De Sciglio, Ignazio Abate and M’Baye Niang.
This means it is almost certain Kaka will start tomorrow’s game with Torino.