Cowboys lose Barber

Posted by ESPN.com's Matt Mosley

As ESPN's Ed Werder reported earlier today, Cowboys running back Marion Barber (toe) didn't make the trip to Pittsburgh and will be replaced Sunday by rookie Tashard Choice. We'd told you earlier in the week how worried the Cowboys' medical staff was about Barber's right pinkie toe -- and he wasn't able to practice all week.

The Cowboys tried to modify Barber's shoe to provide comfort and stability, but nothing seemed to work. Werder reports that the team even commissioned Nike to design a specific shoe at the last minute, but he never had a chance to try it on since it was waiting on him at the team hotel.

Playing in temperatures that should reach the low 20s and the strong possibility of snow, the Cowboys were hoping to lean heavily on the punishing Barber. Now, they must turn to Choice, a fourth-round pick out of Georgia Tech. A longtime NFC scout told me Friday that Choice is well-equipped for running in poor field conditions because he keeps his feet close to the ground.

But the bigger fear for the Cowboys is Choice's lack of experience in picking up the blitz. Even for veteran backs, the Steelers' blitz can be confusing. The absence of Barber could force tight end Jason Witten to stay in and block a lot more than usual. That would take another important weapon away from Tony Romo.

With Barber out, the Steelers should be able to focus more on stopping the Cowboys' passing game. The Cowboys' offensive line feeds off Barber's boundless energy. His ability to tack on yards after contact takes pressure off the line.

With Choice and former Hampton star Alonzo Coleman in the backfield, the line needs to be close to perfect. That's not something that usually occurs against the Steelers' top-ranked defense. I still think it's going to be fairly close, but it's a major setback for the Cowboys.