Le'Veon Bell could be the best running back on the Steelers' roster, and the rookie has yet to take a snap with shoulder pads on, let alone one in an NFL game.

So you would figure it would be only a matter of time before Bell races up the depth chart past lesser pedigree running backs Jonathan Dwyer and Isaac Redman.

That might be the case, but it definitely won't happen until Bell proves he can play at the NFL level when he doesn't have the ball in his hands.

“Around here, if you don't block, you don't play,” Dwyer said.

That's a longstanding unwritten rule around the league when it comes to ball carriers. For running backs coach Kirby Wilson, it is not just tough talk.

“That's anybody. That's any running back,” Wilson said. “You have to be able to protect the quarterback or you won't play. That's not just in Pittsburgh. That's in every NFL city.”

Bell has been brought up to speed quickly on Wilson's top rule over the past month at spring practices and has bought into the importance of the running backs doing their part in protecting $102 million quarterback Ben Roethlisberger. Wilson won't hesitate to keep Bell on the bench, regardless of how well he runs the ball, if he can't trust him picking up a blitzing linebacker.

“I am looking forward to it,” Bell said. “I am a big guy (6-1, 244), too. There are other running backs that are a lot smaller than me who can protect great. I am going to watch technique, learn technique and use my size to my advantage. I know how important it is.”

Even though Bell was an excellent blocker at Michigan State, it's impossible to project that into the NFL. Wilson, who has been coaching running backs in the NFL for 16 years, said the final thing that comes for a rookie is pass protection because there is so much more technique involved than running the ball.