GLENDALE, Ariz. — For Ryan Williams, getting back on the practice field Thursday at University of Phoenix Stadium was a very important step.

After all, given that he’s missed the last few weeks due to injury and, in the process, may have lost his hold on a roster spot, playing is now of the utmost importance.

And he expects to play Saturday when the Cardinals take on the San Diego Chargers in the team’s third preseason game of the season.

“I will be out there,” he said. “I don’t know how many reps I’ll get, but I’ll be out there.

“Hopefully I can get some plays and get in the end zone.”

Williams has dealt with his fair share of injuries, as a ruptured patella tendon cost him his rookie season in 2011 and then a shoulder injury forced him to miss the final 11 games in 2012. Though talented, he does not have enough on film to allow a new coach like Bruce Arians to feel comfortable without seeing what the player can do first-hand.

And that’s why Williams understands the importance of the next few weeks.

“I have about two weeks left — well, a week and a half left — to kind of erase the past couple weeks that I haven’t been out here,” he said. “If everything works well, then it will. But that’s what I’m hoping for, that’s what I’m shooting for.”

And likely what the coaching staff needs to see, especially given the depth at the running back position. Because along with Williams, the Cardinals have Rashard Mendenhall, Alfonso Smith, Stepfan Taylor and Andre Ellington, though only Mendenhall has experienced any kind of success in the NFL. All have shown flashes of ability, and all have been healthy enough to get a good amount of work in this training camp.

Thus, Williams is most definitely behind.

“Every evaluation for him is critical for him now,” Arians said before Williams got back on the field Thursday. “He’s missed so much that I want to see how he does in practice before I put him in a game.

“Hopefully he’ll do as well as I think he will and be able to get out there and play full speed, get tackled.”

Williams did not do as much Thursday as he wanted to, but did get a chance to shake off some of the rust he’s built up by sitting on the sidelines. Where that leaves him for Saturday depends on how he feels over the next couple days, but for now Williams is confident he’ll be ready to go and be effective when on the field.

Asked if he’s confident his leg will allow him to show what he can do, Williams’ response was pretty straightforward.

“Yeah.”

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