The Brewers optioned Gasser to the rookie-level ACL Brewers on Tuesday.
The left-hander seemed likely to stick on the big-league roster with the Brewers expected to utilize a six-man rotation through the All-Star break, but he's instead been jettisoned from the 26-man roster. Gasser still seems likely to get another look with Milwaukee soon since there is a doubleheader on deck next week in St. Louis.