The Astros optioned Salazar to Triple-A Sugar Land on Sunday, Brian McTaggart of MLB.com reports.
Salazar has been up with the Astros as a third catcher since early May, though he's played in just eight games and gone 1-for-7 during his two-plus months in the majors. The 29-year-old is likely to stick with Sugar Land as long as Yainer Diaz and Victor Caratini stay healthy.