AC Milan forward Alexandre Pato has suffered yet another injury setback on the eve of the Serie A campaign.
The Brazil international has struggled with a series of problems in recent times and was restricted to just 11 appearances last season.
And the 22-year-old's difficulties appear to show no signs of coming to an end as he faces another spell on the sidelines.
A statement on Milan's official website read: "AC Milan can confirm that during training on Wednesday, Alexandre Pato reported a problem with his left adductor muscle.
"There will be further medical examinations in the coming days to determine the extent of the damage."
Pato is not the only Milan man on the treatment table with defender Didac Vila having undergone surgery in Barcelona on Tuesday for a groin strain.
The Spanish left-back, who spent last season on loan at Espanyol, faces eight weeks out.
The Rossoneri begin the new season with the visit of newly-promoted Sampdoria on Sunday.