Gusto's contract was selected from Triple-A Sugar Land prior to his start Sunday against the Guardians.
The 25-year-old righty will be making his big-league debut in the final game of the regular season, as the Astros set up their postseason rotation. Gusto logged a 3.70 ERA, 1.27 WHIP and 141 strikeouts in 148.1 innings across 29 appearances for the Space Cowboys. It's not a given that he'll remain on the 40-man roster all offseason, but Gusto has put himself in position to at least serve as organizational rotation depth next year.