NFL Network Insider Ian Rapoport reported Monday that the All Pro is expected to miss an extended period of time due to the injury. Johnson will receive a second opinion, but he's a candidate to be placed on injured reserve.
Good luck overstating Johnson's importance to this offense. The young wonder fried defenses last season with 1,239 yards and 16 touchdowns on the ground to go with another 879 yards and four scores off 80 receptions.
Playing for stretches last year as the most dominant offensive force league-wide, Johnson entered this season hoping to earn 30-plus carries per game in an effort to notch 1,000 yards by land and another 1,000 through the air.
A pipe dream for the vast majority of NFL runners, that goal felt realistic for Johnson before this latest, stunning setback. Early reports suggested the third-year back could return as early as Week 2, but that optimism has faded.
Talked about all August as a bounce-back team, Arizona now rolls into mid-September with burning questions at the quarterback position -- and without the help of their best player.
It's no way to start an NFL season.