King will serve as the Astros' opening pitcher for Wednesday's game against the Giants, Matt Kawahara of the Houston Chronicle reports.
King owns a 3.83 ERA through 49.1 innings this season but has given up 12 earned runs in just his last 9.1 frames. Despite his recent poor form, the Astros will give him his first MLB start. Tatsuya Imai or Ronel Blanco is expected to pitch in bulk relief once King exits, likely after covering the first inning or two.