Sunderland boss Steve Bruce says he won't know the extent of Jordan Henderson's injury until Monday.
Henderson, 19, had been set to undergo scans on Thursday on his ankle having sustained a knock in last week's 1-1 draw with Wigan.
Bruce, though, says it will be the early part of next week before the prognosis is delivered.
Henderson was stretchered off during the second half of the Wigan game but the Black Cats boss is hoping his injury is not as serious as it would appear.
"We haven't got anything back as of yet, but we are keeping our fingers crossed it won't be too bad," he told the club's official website.
"As I've said before, the injury looked quite nasty and we have had to wait until the swelling settled down.
"Hopefully we should have something to report next week and then we can begin treatment."