Sunderland manager Sam Allardyce is uncertain over the fitness of captain John O'Shea for Wednesday's Premier League encounter against Liverpool.
Centre-back O'Shea was in visible discomfort in the closing stages of Saturday's disappointing 4-1 reverse at Manchester City after taking a knock to his calf.
With fellow defender Younes Kaboul already sidelined after tearing his hamstring against Chelsea this month, Allardyce will not take an unnecessary risk with his skipper for the contest at the Stadium of Light.
"Everyone else is okay, but John has a calf injury," he said. "It's not too serious, but maybe serious enough for the exclusion from the squad for the Liverpool game.
"That's something we could do without, with John's experience and knowledge of the game.
"Risking him at less than 100 per cent would be foolish because he could tear that muscle even more and be out for a longer time, like Younes Kaboul. We'll take a view on it but it looks quite doubtful at the moment."
Sunderland's loss at Manchester City left them five points adrift of safety in 19th position, and Allardyce demanded more fight from his team in the aftermath of the defeat.
One plus for Sunderland was the return of Lee Cattermole from a month-long lay-off with a back injury.
And Allardyce believes he will add more steel to Sunderland's midfield.
"I like Lee because he gives us a more competitive edge out of possession," he added.
"We are struggling in defending terms. We aren't getting in people's faces and aren't closing the opposition down enough.
"That's definitely a factor that's been brought to light, particularly in the last two games."