Greg Halford has admitted he has not been playing well enough to be in contention for a place in the Sunderland side in recent weeks.
The former Colchester player, signed from Reading for £3million this summer, has struggled to make the step up to Premier League level.
But Paul McShane's red card at Arsenal and forthcoming three-match suspension has opened up a gap in Roy Keane's defence.
And Halford feels he is gradually getting back to his best and is eager to prove his worth at The Stadium of Light.
He said: "I've not been playing well enough to be in the first team since I've been here.
"But I think I'm coming back to form. I played in the reserves the other night and I've been feeling a lot sharper.
"There's a lot more to come from me and I want to prove that to the manager and the fans.
"Hopefully I can kick on and make a stand for the right-back place while 'Macca' is suspended.
"I couldn't have any argument about being out of the team because of my past form but I aim to change things if I get that chance."