AC Milan playmaker Andrea Pirlo will miss Thursday's UEFA Cup first-round clash against FC Zurich through injury.

Pirlo hurt his right thigh in training on Tuesday and will undergo tests on Friday, the club have confirmed.

Milan refused to speculate as to the severity of the injury, but there are already fears he could be sidelined for up to a month.

Pirlo's absence is a further setback for under-fire Rossoneri coach Carlo Ancelotti, who is also without defender Alessandro Nesta, midfielder Gennaro Gattuso and veteran striker Filippo Inzaghi because of injury.

Milan have lost both Serie A matches this season, leading to suggestions Ancelotti could be sacked.