"Tony picked up a knock during Saturday's game with West Ham and at this stage he is doubtful for the weekend," said David Moyes. "A scan has revealed no lasting damage, which is good news, and it is now just a case of waiting to see if the problem settles down in the next few days."
If it does not then Nigerian defender Joseph Yobo may have to reprise his role as right back for the forthcoming games against Arsenal and Newcastle.