The Pirates designated Villalobos for assignment Monday.
Villalobos will cede his spot on the 40-man roster to catcher/outfielder Henry Davis, whom the Pirates called up from Triple-A Indianapolis in a corresponding move. After being claimed off waivers from the Marlins in April, Villalobos pitched exclusively with Indianapolis, generating a 4.15 ERA and 1.70 WHIP across 16 relief appearances.