Stephane Sessegnon is undergoing treatment on Wearside after pulling out of international duty with Benin.
The Sunderland midfielder was named in his country's squad for Tuesday's World Cup qualifier in Algeria.
But a statement on the club's website confirmed Sessegnon failed to join up with the squad because of an unspecified problem.
It read: "Sessegnon has remained on Wearside for treatment on an injury during the international break.
"He will remain with the club's medical staff ahead of next weekend's game against Manchester United."
Sessegnon reportedly suffered a groin injury during Sunderland's recent defeat at QPR, though he started against Norwich last weekend.