Perry Riley is expected to start at linebacker for the Washington Redskins against the Cowboys on Sunday. It would be his second career start; in his first start, against the Dolphins last weekend, he had four tackles for losses. (John McDonnell/THE WASHINGTON POST)

On a typical day, Redskins players are free after the morning walk-through. Most hit the team cafeteria or find a cushioned seat around Redskins Park where they can relax before practice begins. On Thursday morning, 23-year-old linebacker Perry Riley followed veteran linebacker London Fletcher up the stairs to squeeze in an extra film session. There was a lot to study.

Riley is expected to play in place of Rocky McIntosh again Sunday, this time against the Dallas Cowboys. In his first career start last weekend, Riley posted four tackles for losses, the most by a Redskin since Kenard Lang in 2001. But there's still plenty of room for improvement.

“You could see he’s just one heck of an athlete,” Coach Mike Shanahan said. “But that inside linebacker position, especially in a 3-4 [scheme], takes some time to really get used to. . . . It’s really a learning experience."

Riley was the team's fourth-round draft pick in 2010 out of LSU, but until last weekend, he's been primarily a contributor on special teams, stuck on the depth chart behind McIntosh. Coaches felt McIntosh struggled in recent games and decided early last week to give Riley more first-team reps. By the end of the week, they decided he was ready to start.

Last Sunday Riley was on the field for 64 snaps against the Dolphins and coaches graded every one.

“Think we gave him 15 minuses,” said defensive coordinator Jim Haslett, “which is a lot. I understand it's his first start, but you like to have two or three minuses.”

Still, coaches were pleased enough in Riley's performance to keep him in the starting lineup, and say they've seen great improvement since he joined the team 11 / 2 years ago.

Riley came out of college as a weakside linebacker in a 4-3 scheme. Joining a 3-4 defense and moving inside, Riley had to essentially learn two new positions — the ones occupied by Fletcher and McIntosh.

While Riley was able to learn the basic tenets of the weakside position a year ago, figuring out everything Fletcher does on any given play proved trickier. Shanahan, in fact, said it would be difficult for any rookie.

“You just didn’t know if it was going to take three games, six games or another year,” Shanahan said. “Sometimes it’s the third year when a guy really kind of gets it.”

Coaches didn't want to put Riley in the game until he had both slots figured out. Though Riley began training camp atop the depth chart, the Redskins eventually re-signed McIntosh, which moved Riley into a reserve position. He knew missing organized team workouts during the offseason stalled his progress, and though he studied last season's playbook, that wasn't enough.

“I just tried to learn as much as I could as fast as I could,” he said. “It might have taken me a little longer than I expected, but I feel I finally got there. . . . When it comes to reading it in the book and doing it on the practice field, things happen a lot faster. It's easy to sit in the AC and say, 'Okay, this is what I'm supposed to do.' When you get out there, it's going a million miles per hour.”

To illustrate the growing pains, Haslett points to the Dolphins' “wham” play last weekend. The running play is actually a Joe Gibbs staple, a play that essentially calls for the offense to leave the nose tackle unblocked at the snap. The interior linemen chase after the linebackers, and a fullback will deliver a delayed hit — the “wham” — on the nose.

“I like to have [Riley] go over the top of the wham and Barry [Cofield, nose tackle] become the cutback player,” Haslett said.

Instead, Riley kept charging up the middle.

“He said, 'I got the A-gap,'” Haslett said. “I said, 'I know you got the A-gap, but it was wham, so you're free. You can run over the top.' 'Yeah, but I got the A-gap.'

“I think, 'Holy hell,'” Haslett continued. “But once he sees it and he's on the field and sees what a wham is, he'll understand it the second time.”

The Redskins know there's a learning curve with their young players, and with so many starters sidelined by injuries, coaches also know the final seven games of the schedule may require a bit of patience. But Shanahan and his staff feel they drafted so much raw talent the past two years that the payoff down the road could be big.

According to the coaches' review of game film, Riley had a game-high 14 tackles, nine of them solo. There were many other plays when Riley was around the ball.

“If you watch that football game and you couldn’t see that this guy was a little bit quicker, a little bit faster than everybody else on the field, then you’re not looking at the linebacker position,” Shanahan said.

The Redskins already have decided that Riley will again start for McIntosh Sunday. And Riley is taking the same steps this week. Each day before practice, while many teammates eat and rest for practice, Fletcher and Riley study together. On Thursday, they watched some of the Cowboys' running plays.

“When they break the huddle and he sees the formation, he knows what play they're running,” Riley said of Fletcher. “I'm not exaggerating at all. He knows what's going on.”

To get on the field, the Redskins need Riley to understand both inside positions, and they'll watch him closely again this Sunday to determine whether he's finally ready to line up next Fletcher full-time.