Herrera was scratched from Saturday's Grapefruit League lineup versus the Mets due to knee inflammation, Daniel Guerrero of the St. Louis Post-Dispatch reports.
Herrera had been slated to start at designated hitter Saturday, though his previous few starts had come at catcher, where he's being reintroduced after offseason elbow surgery. Cardinals manager Oliver Marmol said that Herrera will be given 24-48 hours to rest before his status is reevaluated.