The Rays optioned Pruitt to Triple-A Durham on Wednesday, Neil Solondz of the Rays Radio Network reports.
Pruitt's demotion clears a spot on the active roster for Blake Snell (toe), who was reinstated from the 10-day injured list ahead of his scheduled start against the Royals. The 29-year-old worked in relief in Tuesday's 5-2 win, covering 1.2 frames and giving up two runs on three hits.