The Diamondbacks designated Herrera for assignment Friday, Steve Gilbert of MLB.com reports.
The team needed to free up spots on its 26-man and 40-man rosters for the return of Gabriel Moreno (finger), and Herrera is the odd man out. Herrera has managed just a .200/.280/.259 batting line across parts of four seasons at the major-league level, but with teams always looking for catching depth, it's possible he draws interest on waivers.