Washington Redskins safety Brandon Meriweather is expected to miss at least another four weeks to recover from a knee injury, head coach Mike Shanahan said on Monday afternoon.

Meriweather re-injured his left knee during warmups for Week 4's contest against the Tampa Bay Buccaneers when heaccidentally collided with teammate Aldrick Robinson. Robinson was knocked unconscious and suffered a concussion, while Meriweather re-injured his MCL and PCL. Both players were added to the inactive list and did not play in the game.

The Redskins safety had originalled sustained the injuries during the preseason and had yet to make his debut after signing with the team as a free agent this past offseason. He was expected to do so against Tampa Bay prior to re-aggravating the area.

Meriweather signed a two-year deal worth $6 million with the Redskin on March 15. As a member of the Chicago Bears last season, the 28-year-old safety recorded 19 tackles in 11 games played.

This story originally appeared at SB Nation.