Milan's preparations for the derby with Inter suffered another blow when Mark Van Bommel left the Holland camp with an injury.
The midfielder, who arrived from Bayern Munich during the January transfer window, was expected to start the Scudetto showdown next Saturday.
The club's medical staff is on high alert, though, as Van Bommel left the Dutch camp early after pulling up during training.
He was unfit for their victory in Hungary and is now also ruled out of the Oranje's upcoming friendly against the same team.
Initial reports suggest it is a recurrence of his right thigh injury that has caused problems throughout the season.
The Rossoneri are already without the suspended Zlatan Ibrahimovic.
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