SANTA CLARA -- The 49ers on Wednesday claimed outside linebacker Ray-Ray Armstrong off waivers from the Raiders.

The 49ers placed defensive lineman Glenn Dorsey on season-ending injured reserve. Dorsey underwent surgery to repair a torn right ACL on Tuesday.

The Raiders waived Armstrong on Tuesday. He appeared in each of the team’s 10 games this season, including two starts. He recorded 17 tackles on defense and five more on special teams.

In his three-year career, Armstrong has appeared in 41 games (five starts) and registered 47 tackles, one sack, one forced fumble and one fumble recovery with Oakland and St. Louis.

Armstrong, 24, will be reunited with former Raiders defensive coordinator Jason Tarver, the 49ers’ senior defensive assistant/linebackers.

The newest 49ers player was recently in the news for allegedly taunting a police dog before a Nov. 8 game at Pittsburgh. Charges were not filed in connection with the alleged incident.

[RELATED: Raiders LB Armstrong being investigated for taunting police dog]