GLENDALE, Ariz. – Ryan Williams is not oblivious.

The third-year running back has missed the majority of training camp with knee troubles, and at this point his spot on the roster seems tenuous, at best.

Monday morning his head coach, Bruce Arians, said “he needs to start playing,” and Williams said he’s hopeful he’ll be able to play Saturday against the San Diego Chargers.

“With what’s going on with the irritation,” he said. “It can be painful.

“So we’ve been doing some procedures to calm it down and we’re just waiting for that whole thing to just kind of go away. So hopefully it will go away by the end of this week, because I want to play Saturday.”

He may need to.

Though a second-round pick in 2011, Williams has struggled to stay healthy during his brief NFL career. Though he has potential, right now that is all the coaches really have to go off of when evaluating the 23-year-old.

And with four other healthy running backs practicing and playing, Williams likely has some ground to make up in trying to earn a roster spot from a coaching staff with no ties to him. If he misses this next game, as his coach suspects he will, Williams will really be behind the 8-ball, so to speak.

“I will have to make a lot of big plays to erase the time that I have missed,” he acknowledged.

The whole situation, Williams said, has been as frustrating for him as it likely is for the coaching staff. He said if Arians and Co. are upset with him they haven’t shown it, but he would understand if they are.

“I went through the whole spring and OTAs and minicamp with nothing like this,” he said, adding that he worked hard all offseason in an effort to make sure problems like this would not emerge.

But, nothing can change until Williams gets back on the field and starts making plays like many thought he could. He said his teammates are behind him, with guys telling him every day that they are looking forward to his return.

“Whatever I’ve done has left a little print,” he said.

Unfortunately, Williams’ job security is more likely tied to his performance on the field than likability off it, and so far all he’s done is gain 164 yards on 58 carries in five career NFL games. No one is doubting his desire, but questions about his ability to stay healthy and produce are fair.

Should he not improve soon enough, his time in Arizona may come to an unfulfilling close.

However, that’s not something the former Virginia Tech star is worried about, as his main concern is getting healthy and showing what kind of player he is.

“I know my conditioning will kind of be off a little bit because I’ve missed some time, but as far as physically and what I’m capable of doing out there on the field, I won’t miss a step,” he said. “So that’s what I’m hoping to do when I get back out there.”

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