Leiter was optioned to Triple-A Iowa on Saturday, Tim Stebbins of NBC Sports Chicago reports.

EDGE Analysis

Leiter made two relief appearances after being called up May 29, and he allowed three runs while striking out four in five innings. However, he picked up his first major-league win of the season Wednesday against Milwaukee. The right-hander will head back to the minors as part of a move to make room on the active roster for Caleb Kilian, who will start the second game of Saturday's doubleheader against the Cardinals.