New AC Milan signing Lucas Biglia is facing up to a month on the sidelines after suffering a thigh injury.

The 31-year-old joined from Lazio on a three-year deal last month as part of Milan's extensive efforts to overhaul their playing squad for the 2017-18 season.

Biglia played the second half of the Rossoneri's 4-0 International Champions Cup win over Bayern Munich, but has not made an appearance since that clash in Shenzhen.

The club have now confirmed he is unlikely to be available again until the middle of September after sustaining a muscle problem.

"After today's tests, Lucas Biglia was diagnosed with a lesion to his left thigh femoral bicep muscle," Milan said in a statement on Friday. 

"His time of recovery will depend on the evolution of the clinical picture and is estimated to be approximately four weeks."

Biglia will miss Milan's two-legged Europa League qualifier against Shkendija and is likely to be unavailable for the first three Serie A matches of the season against Crotone, Cagliari and Lazio.