Arians didn't give a timeline for how long Johnson would be sidelined, only saying he'd get a second opinion, and that it appears to be the same injury suffered by fellow running back T.J. Logan, who hurt his wrist in August and is expected to miss 12 weeks after undergoing surgery.
According to Adam Schefter of ESPN, Johnson, who suffered the injury in Sunday's loss to the Lions after attempting to make a catch, could miss anywhere from two-to-four weeks to three-to-four months, depending on doctor recommendations.
If there's one player the Cardinals can't afford to lose, it's Johnson. The 25-year-old does it all in Arizona's offense, rushing for more than 1,200 yards and catching 80 passes to go along with 20 total touchdowns a year ago.
The team is thin at the position, with Kerwynn Williams likely to step into the starting role. Williams rushed for just 10 yards on five carries against the Lions. Arians also noted that re-signing Chris Johnson to improve the depth chart was a possibility.