Scott Brown, of the Pittsburgh Tribune-Review, reports Steelers offensive coordinator Bruce Arians said RB Willie Parker (toe) will be the team’s starter when he is healthy because at this point Parker is proven and RB Rashard Mendenhall has not proven himself yet. ‘Willie Parker’s a proven commodity. When Rashard is (proven), then we’ll re-evaluate him. I hope it gets to that problem. I’d like to have those two healthy at the same time,’ Arians said.