The 49ers announced the signing of seven undrafted free agents Monday, including Stanford linebacker Shayne Skov.
Skov was a first-team All-Pac-12 Conference selection and led the Cardinal in tackles with a career-high 109 tackles last season.
The 49ers also signed Southern Cal linebacker Morgan Breslin, Miami (Fla.) tight end Asante Cleveland, New Mexico offensive lineman Dillon Farrell, Southern Illinois quarterback Kory Faulkner, Michigan State offensive lineman Fouimalo Fonoti and Catawba College safety James McCray.
As a result of the signings, the 49ers released linebacker Darius Fleming, receiver DeMarco Sampson and cornerback Dax Swanson.
The 49ers selected 12 players, including first-round pick Jimmie Ward, a defensive back out of Northern Illinois, over the three days of the NFL Draft.
Also Monday, receiver Stevie Johnson passed his physical, which made his trade from the Buffalo Bills to the 49ers official. The 49ers traded a conditional fourth-round pick Friday to the Bills for Johnson. The pick could turn into a third-rounder if Johnson meets certain levels of production.
Johnson caught 52 passes for 597 yards and three touchdowns with the Bills last season.