Johnson left last Thursday's game with a lower back injury. Bills head coach Doug Marrone said Monday that Johnson's status is still uncertain for Sunday's game against the Cincinnati Bengals.
Meanwhile, cornerbacks Stephon Gilmore (wrist) and Ron Brooks (foot) both returned to practice, the first time either has participated in more than a month. It's unclear if either will be ready to play Sunday, but Gilmore was rotated in with the first team during the defensive backs' walk-through at the beginning of practice.
Safety Jairus Byrd, who has been part of the scout team during that walk-through in recent weeks, received some defensive reps in certain packages. At this point, Byrd appears to be a good bet to play Sunday.