Sunderland boss Tony Mowbray has revealed Amad's "body has almost shut down" after a gruelling season at the Stadium of Light.
Amad, who joined Sunderland on a season-long loan from Manchester United last summer, is currently in the middle of his first full campaign at senior level. The 20-year-old has impressed in the Championship - scoring eight goals in 28 games to silence his critics.
He was unavailable for Sunderland's 1-0 win against Norwich last Sunday and will not feature against Sheffield United on Wednesday due to a hamstring injury. Mowbray's confession will concern Erik ten Hag, who may give Amad a chance next term.