Linebacker Perry Riley waited a year and a half to run out with the Redskins' first-team defense as a starter.

Last Sunday in Miami, he finally had that opportunity, replacing Rocky McIntosh in the lineup.

"I've been waiting for this for a long time," the 2010 fourth-round draft pick said. "I'm just trying to take advantage of my opportunity."

And that's exactly what he did on the field, spending all day around the ball. He finished with a share of the team lead in tackles with nine, including four tackles for a loss and a quarterback pressure.

His four tackles for a loss were the most in a single game by a Redskin since defensive end Kenard Lang accomplished the feat in October 2001.

"I'm just out there responding to the plays," he said. "I'm sure when I watch the film, I'll see some areas to fix. But overall, I think I did pretty good for my first start."

Head coach Mike Shanahan agreed after reviewing the game film.

"Perry was very good," he said. "Perry has been doing a good job in practice, especially this year. Last year, like most rookies, it took him a little while to learn our system. But he has earned the right to show us what he can do. He took advantage of that opportunity and had a good game."

Riley made his presence known on the first defensive series, tackling wide receiver Brandon Marshall for minus-four yards on a slip-screen play.

His horse-collar tackle three plays later, which drew a personal foul penalty, served as a reminder that he's got some things to work on.

"I felt like I did some good things out there and made some mistakes as well," he said. "I'm not worried about the things I did well, just worried about the things I need to correct. Fixing them and getting a W, that's why we play this game."

Riley has been a solid contributor on special teams this year, posting six tackles on kick coverage, tied for second-most on the team.

Sunday's performance on defense gives him confidence that he can progress going forward.