The Reds added Petty to their taxi squad ahead of Wednesday's doubleheader with the Cardinals in Cincinnati. Petty is slated to start the second game of the twin bill.
With a rainout Tuesday creating a stretch of six games in five days for the Reds, Petty will step in to serve as a temporary sixth starter. The 22-year-old righty is expected to be sent back to Louisville after the start, but a strong showing versus the Cardinals could solidify his case for joining the Reds on a longer-term basis later on in the season if a more permanent opening in the rotation should emerge. Through his five outings with Louisville this season, Petty owns a 3.52 ERA, 1.30 WHIP and 27:9 K:BB across 23 innings.