Corry Evans is expected to be out for up to a fortnight with a hamstring injury, Lee Johnson has confirmed.
The Northern Ireland international midfielder limped out of Sunderland's weekend win at MK Dons and did not feature in last night's defeat at Burton Albion.
And while the injury is at the lower end of the scale, Sunderland are expected to be without their captain for the rest of August, which would rule him out of this weekend's game against AFC Wimbledon, next Tuesday's Carabao Cup trip to Blackpool, and the home game against Wycombe.
Johnson says the injury is a byproduct of recruiting the 31-year-old relatively late in the window, which meant he was having to build up his fitness by playing games rather than by taking a full part in pre-season.
Johnson said: "It's a tough one with Corry. Because we recruited him late, we were chasing his minutes and he was getting fit through games at 80 percent.
"He's got a low-grade hamstring injury, but we think he is a quick healer so it is probably going to be 10-14 days."
While Evans missed out at Burton, Luke O'Nien returned to the side after missing the MK Dons game through illness.
And Aiden McGeady wore the captain's armband.
