The Royals returned Pennington to Triple-A Omaha following Wednesday's doubleheader against St. Louis.
Pennington didn't pitch in either of Wednesday's games while serving as the Royals' 27th man. He's been a reliable option for Omaha, however, posting a 2.22 ERA and 0.96 WHIP alongside an 81:21 K:BB through 56.2 innings. Should Kansas City need to bring another fresh arm into its bullpen, the 26-year-old southpaw would be a likely candidate for promotion.