The Cubs recalled Hollowell from Triple-A Iowa on Monday.
Hollowell was optioned to Triple-A on Thursday but is back in the majors after the Cubs placed Ethan Roberts (forearm) on the 15-day injured list in a corresponding move. The right-handed Hollowell has appeared in four major-league games this season, allowing three runs on five hits and five walks while striking out three across 4.1 innings.