Porter (back) was a limited participant in practice for the second day in a row Thursday, Teresa Varley of the Steelers' official site reports.
Porter's back injury was added to his designation after it appeared that he was past the issue a day earlier, when he was listed as limited due to conditioning. The cornerback expressed dissatisfaction during training camp because he didn't get a contract extension from the team. There's a lot going on with Porter, and if he can't play Sunday, Asante Samuel should again be in line to step in.