Sunderland left-back Dennis Cirkin will be out of action until the new year because of a hernia injury.
"That's three-six weeks from when he has surgery, which could be another week to 10 days," Sunderland manager Lee Johnson said.
Fellow full-backs Denver Hume and Niall Huggins are also carrying injuries ahead of Tuesday's game at Shrewsbury.
"We can handle the number of injuries, but we tend to get them in the same unit - last year it was centre-backs, this year it's full-backs," added Johnson.