They have a dual job on Sunday. They must protect their injured quarterback and they must block for their new starting running back.
What They Need to Do
This is pretty simple really. The line has to be airtight.
No really. It's that simple. If Bruce Arians constructs the right game plan (three step drops, short passes, quick releases, lots of running mixed in), then all the line has to do is execute long enough for Ben to hit one of his first two reads.
In the running game, all they need to do is give a crack of daylight to Isaac Redman. He has shown the ability to bulldoze through people or bounce it outside, so I'm not worried once he gets loose.
Now there's only one problem. This is a very, very beat up unit. Everyone has had some kind of injury and missed at least one game this year. The key on Sunday will be how well they can suck it up and play. They've done well all year really (at least since Max Starks came back home), and a lot of the hits Roethlisberger has taken have been his fault.
The running game is where the blocking has a lot of room for improvement, but in some ways Redman gives them more room for error because he doesn't cut back or stutter, he just goes.