49ers coach Kyle Shanahan said earlier this week he expected to be short-handed against the Rams.
The 49ers did get one player back Friday.
They announced they have activated defensive tackle Javon Kinlaw from the reserve/COVID-19 list.
The 49ers also announced they signed veteran receiver Jordan Matthews to the practice squad, waiving receiver Chris Finke to make room.
Matthews spent part of the season with the 49ers in 2019 and appeared in one game.
In six seasons with the Eagles, Bills and 49ers, Matthews has appeared in 73 games with 46 starts. He has made 274 receptions for 3,288 yards and 22 touchdowns.