The Astros optioned Mushinski to Triple-A Sugar Land on Thursday, Chandler Rome of the Houston Chronicle reports.
Mushinski gave up three earned runs on five hits and a walk while striking out seven in 5.1 innings out of the Houston bullpen following his April 16 call-up from Sugar Land. He'll lose his spot on the active roster with the Astros reinstating closer Ryan Pressly (knee) from the injured list in a corresponding move.