Inter Milan are waiting to discover the severity of a shoulder injury suffered by Yuto Nagatomo in Saturday's game against Celtic, with some reports suggesting he could be sidelined for two months.
The Japan international was stretchered off just ten minutes into the match in Dublin, which Inter won 2-0, and he has now flown back to Milan for further assessment.
He seems certain to miss the Italian Super Cup clash with AC Milan in Beijing at the weekend, but there are concerns he could be facing a much longer lay-off.
If he has dislocated the shoulder and requires surgery the full-back may be out until the end of September and Inter will be anxious to discover the results of scans.
"Unfortunately it was a risk we knew to have in these summer tournaments," head coach Gian Piero Gasperini told the club's official website.
"For Beijing we will surely miss Nagatomo. In the next hours we will evaluate whether we should recall a few players we left home after the Copa America."