Heller was optioned to Triple-A Scranton/Wilkes-Barre on Wednesday.
Heller will head back to the minors after making just one appearance for the Yankees; he recorded one out while allowing a walk and a hit. He'll stick with the RailRiders, with whom he owns a 2.60 ERA and 35:11 K:BB through 27.2 innings this season, until the Yankees need further bullpen help. Ronald Herrera was recalled to take his place in the bullpen.