AC Milan striker Alexandre Pato broke down again in their Champions League defeat to Barcelona.
Pato made his comeback for the first time since February 25, but lasted only 13 minutes on the field before limping off again.
"He felt another twinge on the back of his thigh and the medical staff will evaluate it. If he has hurt himself again, then that will be a problem, as the poor lad has been carrying these problems for two years."