The Redskins have placed defensive end Kedric Golston on season-ending injured reserve, the team announced on Saturday.
In addition, the Redskins signed safety Sha'reff Rashad and defensive lineman Joe Joseph from the practice squad and released defensive lineman Jeremy Clark.
Golston has been slowed by groin and elbow injuries in the last few weeks and would not have been available to play in the Redskins' last two games.
The fifth-year player had started all 13 games he participated in during the 2010 season. He finished the season with 57 tackles (32 solo), seven quarterback hurries and two passes defended.
Rashad, 6-0 and 198 pounds, adds depth to the Redskins' injury-plagued secondary. Reed Doughty is sidelined with a concussion and Kareem Moore is slowed by a knee injury.
Rashad signed with the Redskins' practice squad on Nov. 8.
He was previously with the New York Giants. In four preseason games with the Giants earlier this year, he compiled seven tackles, one special teams tackle, one interception and two passes defended.
Rashad entered the NFL as an undrafted rookie free agent with the Giants on May 8, 2009.
Rashad played college football at Central Florida, where he appeared in 49 games. He compiled 257 tackles (188 solo), one sack and 14 interceptions. He finished with 72 tackles (54 solo), five interceptions, 10 pass breakups and two tackles for loss during his senior season.
He is a native of Jacksonville, Fla., where the Redskins play against the Jaguars on Sunday.
Joseph, a 6-2 and 315-pound rookie, signed with the Redskins' practice squad on Dec. 15.
He spent time on the New York Giants' practice squad earlier this year and was on the Tennessee Titans' roster during preseason.
Joseph orginally entered the NFL as an undrafted rookie free agent with the Titans.
Joseph played collegiately at Miami (Fla.), where he appeared in 37 games with 25 starts. He finished his career with 71 tackles, 1.5 sacks, 13 tackles for loss, eight quarterback pressures, one pass defended and one fumble recovery.
He is a native of Orlando, Fla.