The San Francisco 49ers currently only have three outside linebackers available: Ahmad Brooks, Eli Harold, and Tank Carradine. Aaron Lynch, suspended for the first four games, will eventually return, but the 49ers do not possess extreme depth at this position.
This lack of depth made it all the more surprising that the 49ers released Marcus Rush, an outside linebacker who showed significant promise throughout the preseason.
Rush led the NFL with six sacks, forced two fumbles, and garnered an interception in his preseason action, per NFL.