Medina was optioned to Double-A Reading on Saturday, Meghan Montemurro of The Athletic reports.
The 22-year-old spent the start of spring with the big-league club but was never a candidate for a roster spot, as he's yet to pitch above High-A. He'll move up a level this season after posting a 4.12 ERA with strong peripherals (a 26.1 percent strikeout rate, 7.6 percent walk rate and 50.2 percent groundball rate) for High-A Clearwater last season.