Sunderland goalkeeper Simon Mignolet is likely to be out of action for two months after fracturing an eye socket.
The injury occurred when the Belgian international collided with Emile Heskey during his team's 2-2 draw with Aston Villa on Saturday.
The 23-year-old initially underwent surgery on a broken nose and was expected to be out for a couple of weeks.
However, further damage to his eye socket was discovered.
"Rather than a couple of weeks, it will be a couple of months," Sunderland manager Steve Bruce told BBC Newcastle.
"The broken nose is as bad as I've ever seen, and he's fractured the eye socket as well."
Bruce has decided to recall Keiren Westwood from his loan spell at Bury as a result.
Westwood is likely to make his first Premier League start at Manchester United on Saturday, as first-choice goalkeeper Craig Gordon is also injured.
