Johnson reverted to the 49ers' practice squad Monday, Nick Wagoner of ESPN.com reports.
With the 49ers backfield depleted by injuries, Johnson was called up to the active roster but didn't make an impact on offense this past Sunday against the Packers, seeing only nine snaps on special teams. Trenton Cannon also was used exclusively on special teams (17 snaps), while Trey Sermon (41 snaps on offense) and Kyle Juszczyk (52 snaps) were the other backs to see action. There's hope Elijah Mitchell (shoulder) is able to return next Sunday versus the Seahawks, which would likely mean no elevation for Johnson in Week 4.