Johnson (knee) did not participate in Thursday's practice, Joe Buscaglia of The Athletic reports.
Johnson exited Saturday's practice early with a knee injury and has not returned to the field since. Thursday marks the running back's fourth consecutive missed practice, and there does not appear to be a return date in sight. If Johnson's knee injury is severe, the Bills could be waiting for cutdown day to place him on injured reserve with a designation to return during the regular season.