Martinez will make his MLB debut Tuesday, as he's scheduled to be called up from Triple-A Las Vegas to start the nightcap of a doubleheader against Detroit, Matt Kawahara of the San Francisco Chronicle reports.
Martinez came over from the Padres in early April as part of the return for Sean Manaea. He's struggled in five starts for Las Vegas this season, posting a 7.45 ERA and a 10.3 percent walk rate, though he's at least struck out 28.7 percent of opposing batters.