Perry Riley makes a tackle last season against Pittsburgh. (Gene J. Puskar/The Associated Press)

RICHMOND — Redskins linebacker Perry Riley tested himself during practice and noticed a trend. He was getting the plays right – not just for himself but for the entire defense. It was a big step in his development and it’s why Riley is confident that, should something happen to London Fletcher, he could at least handle part of his role.

Riley would remain at his linebacker spot – the “Jack” linebacker. But part of what makes Fletcher’s job at the “Mike” linebacker difficult is needing to know not only his responsibility, but everyone else’s. It’s part of the job description, but it’s also something Fletcher excels at doing, thanks to his study habits.

“I definitely know it,” Riley said. “Towards the middle and back end of last year I was ready to do it then, but London never got hurt.”

With Keenan Robinson sidelined and Lorenzo Alexander in Arizona, the Redskins’ inside linebacker unit has been thinned. Bryan Kehl has been a special teamer in his four-year career (with nine starts) and Roddrick Muckelroy, a 2010 fourth-round pick of the Bengals, has played in 19 NFL Games with no career starts. Wednesday night, the Redskins signed former Buffalo Bill and Green Bay Packer Nick Barnett.

Whether or not the Redskins would need Riley to handle expanded duties would depend on who else is next to him, should Fletcher be sidelined at all. But the belief is that Riley could do it if necessary.

“He knows the Jack linebacker like the back of his hand and there are times where he’s essentially the Mike linebacker, so he knows [that] position,” Fletcher said. “There have been times in the past where he’s had to make the calls so he can definitely do that.”

Riley, entering his fourth season and third as a starter, is a soft-spoken player, which is why he said one of the harder adjustments for him would be “just being the vocal leader.”

“At the Jack, I just listen to the call and play what I hear,” Riley said. “But when you’re the Mike, you have to line up everybody and make sure everyone gets the right call and is doing the right thing.”

It took time for him to feel confident doing this. He finally noticed a change last season. Because Fletcher was nursing a sprained ankle much of the year, and was unable to practice most of the second half of the season, Riley needed to improve in this area. With Fletcher now 38, and coming off ankle and elbow surgery, it’s wise to prepare someone to take over the play-calling duties.

“Instead of me listening to what London calls, I’m calling the plays myself in my head, to be able to rely on myself,” Riley said. “When you get in front of 95,000 people you can’t really hear everything London calls so it’s good to know it yourself. That’s when I realized I was ready. I started doing it in practice and it carried over into the games.”

Related: John Keim departs for ESPN

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What’s ahead:

● Thursday’s practices are at 10 a.m. and 3:20 p.m. If you’re headed to Richmond, check our our guide to training camp for tips on getting autographs, where to park and things to do after the session is over.

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