The Mariners designated Zavala for assignment Saturday.
Zavala was selected to the active roster Tuesday to provide additional depth behind the plate, and he'll now be pushed back off the 40-man without appearing in a game for Seattle. The 30-year-old backstop passed through waivers unclaimed when he was DFA'd in June, and it's likely he does so again this time around. Emerson Hancock was recalled from Triple-A Tacoma in a corresponding move.