Long snapper Nick Sundberg missed a portion of last season with a broken arm, and now will miss the remainder of this year with a torn meniscus in his right knee. (John McDonnell/The Washington Post)

The Washington Redskins have lost two key special teams players to season-ending injury, coach Mike Shanahan said on Monday. Linebacker Bryan Kehl will miss the remainder of the year with a torn anterior cruciate ligament in his left knee. Meanwhile, long snapper Nick Sundberg tore the meniscus in his right knee and also will be placed on injured reserve.

Kehl, one of the team’s top defenders on the punt and kickoff coverage units, injured his knee during the second-quarter punt that Dallas’s Dwayne Harris returned 86 yards for a touchdown. Kehl was running downfield and appeared to potentially have an angle on Harris when he collapsed around the 23-yard line despite not having sustained any contact from any other players.

Kehl said on Sunday that he “just felt something pop.” After the game, he said that he didn’t feel any pain in the knee just standing up. But he did admit there was some swelling in the knee and that he did experience some stiffness and soreness when he tried to bend it.

Kehl spent portions of last season with the Redskins, and this past offseason, the sixth-year pro re-signed with the team on a one-year contract. Kehl led the team with five special teams tackles.

Meanwhile, Sundberg tore his meniscus while knocking Harris out of bounds on a third-quarter punt return. Sundberg revealed on Monday that he actually had partially torn his meniscus in Washington’s victory over Oakland in Week 4. But on Sunday, he completely tore the meniscus against Dallas.

Sundberg hadn’t been listed on Washington’s injury report leading up to the Dallas game.

Describing the play on Sunday night, Sundberg said, “I didn’t really feel anything – but I tried to get up, and couldn’t put any pressure on it. It was kind of one of those real awkward plays.”

Sundberg this past offseason was a free agent and returned to the team after signing a four-year deal.

The Redskins hadn’t made any signings to fill either players’ roster spot as of Monday afternoon, but Shanahan said they would do so within the next day or so.

In other injury-related news, Redskins coach Mike Shanahan commented on what happened with rookie cornerback David Amerson, who left Sunday’s game with a concussion while running downfield on kickoff coverage. Dallas linebacker Cameron Lawrence hit Amerson with a blindside hit from the right. Amerson went down in a heap. Shanahan said that Amerson needed to have hit the hole faster rather than hesitate and make himself a sitting target for Lawrence.

“It was definitely helmet-to-helmet,” Shanahan said. “David, of course in that position, he’s going to learn in time that he’s got to hit that hole a little bit harder. He can’t wait. He’s got an excellent opportunity to go in there and make the play, and that’s just a guy with a little inexperience. Next time he’s in that position, he’ll make the tackle.”

Harris took that kickoff 90 yards, running through the lane that Lawrence created when he took out Amerson.

Amerson will be monitored on a daily basis for lingering concussion-like symptoms.

Have a Redskins question? E-mail Mike Jones at mike.jones@washpost.com with the subject line “Mailbag question” for him to answer it in The Mailbag on Tuesday.

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