The Astros designated Amaya for assignment Saturday, Matt Kawahara of the Houston Chronicle reports.
With Hector Neris joining the Astros' bullpen, Amaya will lose his spot on the 40-man roster. The 25-year-old infielder went 0-for-1 during his lone game with Houston in May, and he's slashed .223/.313/.336 across 291 plate appearances at Triple-A Sugar Land.