Junis was optioned to Triple-A Omaha on Sunday, Josh Vernier of 610 Sports reports.
Junis picked up a relief win during his last outing, but he's posted a 5.19 ERA and 1.44 WHIP in 34.2 innings across 15 innings (five starts) to begin the year. He'll head to the minors as part of a shuffle to make room for Jackson Kowar, who will be called up to make his major-league debut as Monday's starter against the Angels.