Sunderland boss Martin O'Neill has confirmed skipper Lee Cattermole is likely to be on the sidelines for some time with a knee injury.
Cattermole was hurt in the early stages of the scoreless draw with Queen Park Rangers at the Stadium of Light last Tuesday.
The midfielder appears to have damaged medial ligaments, which would rule him out for up to a couple of months, and he has travelled to London to seek the opinion of a specialist.
O'Neill said: "Lee Cattermole has travelled to London today to see a specialist. We don't have a proper update yet but he's going to be out for some time."
Meanwhile, O'Neill insists his squad are in good heart as they prepare to travel to in-form Norwich on Sunday, despite Sunderland's recent poor run of form.
"The players are still in very good spirits and looking forward to the game at the weekend," O'Neill added. "Norwich are on a good run.
"They have won a couple of big games at Carrow Road where they are particularly strong with wins over Manchester United and Arsenal and I think they'll be looking at any points away from home are bonuses for them.
"They will certainly be up for the job this weekend but I can promise you so will we."