Johnson entered the team's opener against Central Michigan as the Wolverines' second-string running back, and had two carries for nine yards before leaving the game in the second half with the injury.
The running back was one of six running backs on Michigan's depth chart Saturday, and figured to play a key role in the Wolverines' offense this season behind starter Fitz Toussaint.
Redshirt sophomore Justice Hayes and junior Thomas Rawls were listed behind Johnson on the depth chart, and could move up in Johnson's absence. Rawls was the primary backup to Toussaint last season. Freshmen Derrick Green and De'Veon Smith are also expected to receive carries. Green may be the most likely option to replace Johnson, as he ran 11 times for 58 yards against Central Michigan.
Johnson was a three-star recruit coming out of Pioneer (Mich.), according to the 247sports composite rankings. He was a late addition to the Wolverines' 2012 class who played high school ball about two blocks away from Michigan Stadium.
Be sure to check out Maize n Brew for more.