The Mariners outrighted Hernandez to Triple-A Tacoma on Sunday.
Hernandez will report to the Mariners' Triple-A affiliate after he cleared waivers upon being designated for assignment Thursday. The right-hander has produced a 5.40 ERA and 1.59 WHIP with 39 strikeouts over 43.1 innings across 29 appearances at the big-league level between the Rangers and Mariners this season.