Ghana midfielder Sulley Muntari will be out for six months after undergoing a knee surgery.
The 27 year-old player, who joined AC Milan in January, ruptured anterior cruciate ligaments on Monday whilst playing in an exhibition game while on holiday in Accra.
However, he has undergone successful operation on Wednesday performed by Professor Schonhuber in Milan.
"AC Milan communicate that Sulley Muntari has undergone surgery for the reconstruction of the anterior cruciate ligament in his left knee.
"The recovery time is around five to six months, excluding complications," read a club statement.
Muntari scored three goals in 13 Serie A appearances last season.