The San Francisco 49ers announced they have placed LB Ray-Ray Armstrong on the Injured Reserve List and promoted LB Shayne Skov to the active roster from the team's practice squad. The 49ers have also signed LB Curtis Grant to the team's practice squad.

Armstrong (6-3, 220) was originally claimed off of waivers by San Francisco from the Oakland Raiders on November 25, 2015. He appeared in each of the team's first two games this season and registered nine tackles, two passes defensed, one fumble recovery and the first interception of his career.

Skov (6-3, 197) was signed to the team's practice squad on September 4, 2016. In 2015 with San Francisco, he appeared in 15 games and registered four tackles on special teams. Skov will wear number 56.

Grant (6-2, 240) originally signed with the San Diego Chargers as an undrafted free agent on May 2, 2015 out of Ohio State University. Following his release from San Diego on August 30, 2015, he was signed to the Atlanta Falcons practice squad on December 15, 2015, where he spent the remainder of the season. On April 1, 2016, he signed as a free agent with the Tennessee Titans, spent training camp with the team and was later released on September 2, 2016. On September 5, he was signed to the Oakland Raiders practice squad and was recently released by the team on September 14.