Herrera (back) will begin a rehab assignment at Triple-A Memphis on Thursday, Lynn Worthy of the St. Louis Post-Dispatch reports.
Herrera is slated to catch five innings with Memphis on Thursday for his first game action since being placed on the IL on June 22 due to back soreness. Even when healthy, it's unclear if Herrera will stick around with the Cardinals considering Willson Contreras and Pedro Pages are both active.