TEMPE, Ariz. -- The Arizona Cardinals will be without running back Chase Edmonds against the San Francisco 49ers on Thursday night, but a decision has yet to be made public about whether running back David Johnson will be able to play.
Coach Kliff Kingsbury ruled Edmonds out on Wednesday afternoon as he continues to work through a hamstring injury. Johnson, however, was listed as questionable with an ankle injury. He took part in the open portion of practice earlier in the day, going through the team stretching period as well as positional drills.
"David, still working through it," Kingsbury said.
The Cardinals' running back depth chart Thursday night will include three players not on the roster at the start of last week: Zach Zenner, Alfred Morris and Kenyan Drake.
The plan against the visiting 49ers is to use a "running back by committee," Kingsbury said.
"We'll kind of get it rolling and see how it goes," he added.
Arizona traded for Drake on Monday after signing both Zenner and Morris last Wednesday. Morris will be active against the Niners, Kingsbury said, after being a healthy scratch against the New Orleans Saints in Week 8.
Drake, who arrived in Arizona at 4 p.m. MT Monday and had a playbook in his hands by 7 p.m., has been forced to learn the Cardinals' scheme on the fly. Kingsbury admitted it's challenging to have a new running back playing with such a short time in the system, but it's up to the Arizona coaching staff to have Drake do only what he can handle and feel comfortable with.
"He's been great," Kingsbury said. "Really picked things up quickly. He's played in several different offenses but he's been grinding away at it since he got here. The first night he got here, he was in meetings. Excited to see what he can do. He's got some explosiveness. He's a very talented player, and we're going to get him in the game in some capacity and see where it goes."