Defender Kenny Cunningham has joined Sunderland's lengthy injury list after picking up a hamstring strain.
The 35-year-old is currently undergoing intensive treatment at the Black Cats' warm weather training camp, but is expected to be out of action for around three weeks.
Manager Roy Keane told the club's official website: "Kenny has a hamstring strain and is working with the physios out here. We'll be back on Thursday and we'll see how it is then."
Cunningham will miss the trips to Preston and Stoke, but may be able to return against Barnsley on October 21.
Sunderland already have Graham Kavangh, Stephen Wright, Steve Caldwell, Stephen Elliott and Daryl Murphy sidelined by injury.