Johnson (groin) didn't take part in Monday's practice, Kent Somers of the Arizona Republic reports.
The manner in which Johnson went to the ground Sunday was worrisome, to say the least, so the fact he's dealing with a groin concern was welcome news. Nevertheless, the Cardinals have three days to prepare for Thursday's contest at San Francisco, making a complete rehab difficult to comprehend. In order to fill the potential void in the backfield, the team has re-signed Kerwynn Williams to serve as a depth RB option behind starter David Johnson and primary reserve (for now) Andre Ellington.