The Guardians optioned Heuer to Triple-A Columbus on Saturday.
Heuer pitched 1.2 shutout innings during Game 1 of Saturday's twin bill, but he'll now be sent down to the minors so the Guardians can add a fresh arm to their bullpen in the form of Will Dion. Heuer now owns a 4.66 ERA through 9.2 frames with Cleveland this season and could return to the big club later this year as bullpen depth.