The Pirates optioned Priester to Triple-A Indianapolis on Wednesday.
With Paul Skenes in the fold and Bailey Falter pitching well enough to keep his rotation spot, Priester becomes the odd man out. He holds a 4.33 ERA and 17:10 K:BB over 27 innings covering five starts with the big club this season. Priester will join the Indianapolis rotation and likely will be the first to be called upon when the Pirates need a starter.