The Rays activated Mejia (knee) from the 10-day injured list and designated him for assignment Tuesday, Marc Topkin of the Tampa Bay Times reports.
Mejia completed his rehab assignment after recovering from a left knee sprain and seemingly was poised to rejoin the Rays' 26-man active roster. However, the team has decided they prefer what Rene Pinto provides as the No. 2 catcher behind Christian Bethancourt. Mejia could clear waivers based on his $2.16 million salary this season, but the former top prospect is under team control for another season, so it's possible he garners interest from other organizations.