Redskins safety Brandon Meriweather Safety Brandon Meriweather was helped off the field after injuring his left knee against the Chicago Bears Aug. 18. He reinjured the knee in practice Monday. (Charles Rex Arbogast/Associated Press)

Redskins starting strong safety Brandon Meriweather missed practice Wednesday after spraining the MCL and PCL in his left knee during practice Monday, coach Mike Shanahan said. 

Shanahan said Meriweather, who had recovered from an injury to the same knee suffered in Week 2 of the preseason, will miss two to four weeks of action. He said Meriweather came down awkwardly on his knee during Monday’s practice.

Shanahan didn’t name a replacement starter, but second-year pro DeJon Gomes said he got significant time with the first team on Wednesday.

Shanahan said Brian Orakpo (shoulder) and Kory Lichtensteiger (knee) both practiced fully. Nose tackle Chris Baker was limited with a sprained ankle.

Shanahan said Roy Helu Jr. and Evan Royster “seem to be coming on right now” after being injured in the preseason. Those two, plus Alfred Morris, continue to be evaluated, and a starter won’t be named until “right before the game,” Shanahan said.