AC Milan midfielder Alberto Aquilani has been ruled out of Sunday's Milan derby against Inter with an ankle injury.
The 27-year-old hurt his left ankle in training, forcing him to miss last weekend's win at Atalanta, and the Italian international is set to face a month on the sidelines, the club announced on Friday.
Aquilani, on loan from Liverpool, underwent surgery on the same ankle in 2009 prior to his move to England.
Meanwhile, Gennaro Gattuso has suffered a setback on his road to recovery from a career-threatening eye condition.
The 33-year-old was diagnosed with sixth nerve palsy following a collision with teammate Alessandro Nesta in September and further tests have revealed a muscle weakness that will keep him out of action indefinitely.
Gattuso has featured just twice this season for the rossonieri, including the club's 2-1 win over Inter in the Italian Supercup.