The 49ers placed LB Travis LaBoy and PK Joe Nedney on injured reserve Saturday.
Nedney sustained a right knee strain and a bone bruise during a Week 10 game against the Rams. Shane Andrus had replaced him before Jeff Reed replaced Andrus.
LaBoy suffered a knee injury in Thursday night's loss to the Chargers. He is tied for second on the team in sacks with five.
Taking their spots will be TE Colin Cloherty and DT Will Tukuafu, both promoted from the practice squad.