AC Milan will likely have to make do without the services of Alessio Romagnoli in Sunday's derby clash with Inter due to a groin injury.
The centre-back suffered a knock in Tuesday's 0-0 international friendly draw between Italy and Germany and made way for Davide Astori at half-time.
It is not yet known how long the 21-year-old will be out of action, but a return in time to face Inter seems unlikely at this stage.
"Milan announce that Alessio Romagnoli suffered a groin injury during the match with Italy on Tuesday night," a brief statement on the club's website reads.
"The player will undergo further medical examination in the next few days."
Romagnoli, 21, has been a key figure for Milan this term, making 11 Serie A appearances.
Milan sit third in the table with 25 points from 12 games, five behind leaders Juventus but eight ahead of Inter.