Coach Jeff Fisher reportedly notified his team about the change at a team meeting on Wednesday.
In last week's loss to the Arizona Cardinals, Davis completed 17 of his 30 pass attempts for 216 yards with one touchdown and two interceptions. The previous week, Davis threw for only 102 yards with a touchdown and two interceptions.
The Rams, who rank 26th in the league with 212.8 passing yards per game, are 3-6 this season and in last place in the NFC West.
- Chris Johnson