Redskins' running back committee: Roy Helu, left, Evan Royster, center, and Tim Hightower. Royster will start Thursday against the Bills and share carries with Helu. Hightower is out. (John McDonnell/THE WASHINGTON POST)

Royster and fellow second-year back Roy Helu Jr. have alternated days as the starter, and veteran Tim Hightower continues to work his way back from ACL surgery in a limited capacity. Hightower will not play on Thursday.

Shanahan said that although Royster will start, Helu will handle nearly as many carries. The coach estimated each would see 15 to 20 plays.

Shanahan has observed Royster and Helu in practices, but the coach said those performances are only part of the equation. The preseason games will help Redskins coaches get a better idea of where the two stand in the positional battle.

“You kind of get a feel, but until you actually see a running back live, it’s hard to evaluate a guy,” Shanahan said. “You get a feel, but you really don’t know for sure.. . .It’s always nice to get in game situations and see how they play.”

Shanahan said that in addition to ball-carrying duties, Royster and his fellow backs will be evaluated on their pass protection skills, which generally take a while for a young running back to master.

Royster said he expects to be busy on special teams as well. He will be playing on the kickoff, kick return and punt return teams. It will mark the first time that Royster will have so many responsibilities.

“Hey, anything that’s going to help me make the team,” he said. “I’m excited. I get to play on three special teams, as well as offense. It’ll be good to get back into playing football against someone other than my teammates.”

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