49ers sign LB Ray-Ray Armstrong off waivers from Raiders

SANTA CLARA, Calif. -- The San Francisco 49ers claimed linebacker Ray-Ray Armstrong off waivers from the Oakland Raiders on Wednesday and placed defensive lineman Glenn Dorsey on season-ending injured reserve in the corresponding roster move.

Armstrong appeared in 10 games with the Raiders this season, starting two, and had 17 tackles on defense and five more on special teams. He was waived by Oakland on Tuesday.

Armstrong was investigated for taunting a police dog at Pittsburgh’s Heinz Field during pregame warmups Nov. 8 after he reportedly “lifted his shirt, pounded on his chest and began barking at the dog as he was heading toward the field for the game.” Armstrong could have faced a third-degree felony for taunting the dog but was not charged.

The Niners hope he can help a defense that could not stop the run (255 rushing yards by the Seattle Seahawks last weekend) or the pass (Russell Wilson completed 82.8 percent of his passes) as they prepare for the Arizona Cardinals this weekend.