Martin was recalled from Triple-A Reno and will start Sunday against the Nationals.
The 26-year-old was previously announced as the starter for Sunday's contest, and he's now officially been added to Arizona's active roster. Martin has come out of the bullpen in his five big-league appearances this year and has a 4.40 ERA and 14:6 K:BB across 14.1 innings, though he's worked as a starter in the minors and delivered eight shutout innings for Reno in his last start.