San Francisco 49ers place LB Ray-Ray Armstrong on IR

The San Francisco 49ers placed linebacker Ray-Ray Armstrong on the injured reserve list Wednesday due to a pectoral injury.

Armstrong suffered a torn chest muscle in the second half of Sunday's 46-27 loss at the Carolina Panthers.

The 49ers promoted linebacker Shayne Skov to the active roster from the practice squad. The team also signed linebacker Curtis Grant to the practice squad.

The 6-foot-3, 220-pound Armstrong was originally claimed off waivers by San Francisco from the Oakland Raiders on Nov. 25. 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.

The 6-3, 197-pound Skov was signed to the practice squad on Sept. 4. In 2015 with San Francisco, he appeared in 15 games and registered four tackles on special teams.

The 6-2, 240-pound Grant originally signed with the San Diego Chargers as an undrafted free agent on May 2, 2015, out of Ohio State.

Following his release from San Diego on Aug. 30, he was signed to the Atlanta Falcons' practice squad on Dec. 15, spending the remainder of the season. On April 1, he signed as a free agent with the Tennessee Titans, spent training camp with the team and was later released on Sept. 2. On Sept. 5, he was signed to the Oakland Raiders' practice squad and was released on Sept. 14.