Stephenson was diagnosed with a concussion and will be placed on the 7-day injured list Wednesday, Bobby Nightengale of The Cincinnati Enquirer reports.

EDGE Analysis

Stephenson suffered the injury while tagging out Luke Voit in a collision at home plate during the opening frame of Tuesday's loss to the Padres, and he'll be out for at least a week while going through the concussion protocol. Aramis Garcia should step in as Cincinnati's primary backstop in the meantime, and the team will need to promote another catcher to serve as the backup.