Fitzgerald Cecilio

The already depleted Washington Redskins defense experienced additional setbacks as two of their reliable defenders will be out for the remainder of the season with various injuries.

Outside linebacker Brian Orakpo suffered a torn left pectoral muscle after sacking quarterback Sam Bradford while Adam Carriker tore a quadriceps tendon near his right knee in a 31-28 loss to the St. Louis Rams, according to coach Mike Shanahan.

Shanahan said they will both undergo surgery with Carriker facing a five-month recovery period and four months for Orakpo.

This means the Redskins will play their home opener against the Cincinnati Bengals without four defensive starters. Cornerback Josh Wilson left the game against the Rams with a concussion while safety Brandon Meriweather is still sidelined with a knee injury.

"Obviously he's a guy that can do it all," Shanahan said, referring to Orakpo. "He can cover. He can rush. He can play the run. He's a very physical, very smart, team player. He's all the things you look [for] in a Pro Bowl player. And obviously we'll miss him."

Shanahan said he will look at fourth-year pro Rob Jackson and fifth-year pro Chris Wilson during practice and choose who will take Orakpo's outside linebacker spot later in the week.

"It's a big opportunity, not only for myself but for any backup," Jackson said. "You're a backup in a position waiting for that day or that game that you actually start a game. We'll see how the week goes and see what decisions they make."

Jarvis Jenkins, a second-year pro who missed all of his rookie season because of a torn anterior cruciate ligament in his right knee, takes over Carriker's spot at left end.

"Last year when I tore my ACL, everybody had to step up and play a role," Jenkins said. "We brace for times like this. That's why everybody gets reps. That's why everybody watches film. When one guy goes down, like Coach Shanahan says, we shouldn't have a dropoff."

Redskins Lose Brian Orakpo & Adam Carriker to Season-Ending Injuries - NFL 2012