The Reds optioned Franco (elbow) to Triple-A Louisville on Wednesday.
Franco will report back to Triple-A after he served as the Reds' 27th man for Wednesady's doubleheader with the Guardians. He was active for Game 2 of the twin bill and worked in bulk relief in the Reds' 2-0 victory, earning his first big-league win while striking out two and allowing one hit and two walks over 3.2 scoreless frames before exiting in the seventh inning due to right elbow discomfort. He'll likely undergo further testing before the Reds have a better idea regarding the extent of his injury, but Franco could be at risk of landing on Louisville's 7-day injured list if he isn't ready to go for his next turn through the rotation.