The defender did take a blow to the head during last Monday’s 3-0 home defeat against Everton but it is understood he was not suffering from concussion.
Even team-mate Lee Cattermole insisted he had no idea what was wrong with Van Aanholt.
“I don’t know anything about it,” said the Black Cats skipper. “It was obviously a blow that we did not expect but it happens.”
Moyes is due to face the media this morning ahead of tomorrow’s EFL Cup tie at QPR.