Packers coach Mike Sherman today said that a magnetic resonance imaging test revealed a torn anterior cruciate ligament in Poppinga's left knee. He sustained the injury while covering a kickoff in the fourth quarter. Poppinga was helped off the field and did not return.
Sherman said today that the injury requires an 8- to 10-month rehab schedule.
Poppinga started his first game at outside linebacker against the Lions on Sunday night. He finished with four tackles. Poppinga also is Green Bay's leading tackler on special teams with 21.
Na'il Diggs, whom Poppinga started ahead of on Sunday, is the Packers regular at the strong-side linebacker position but he has battled MCL injuries to both knees this season. Rookie Roy Manning stepped in for Manning when Poppinga was injured against the Lions with Diggs playing a reserve role.
The Packers already have 10 players on injured reserve, including rookie linebacker Kurt Campbell.