The Pirates activated Priester (lat) from the 15-day injured list Tuesday.
Priester has been shelved since June 6 due to a right lat injury, but after making a pair of rehab starts, Pittsburgh determined he was ready to rejoin the active roster. The 24-year-old completed five innings in his latest rehab outing and could take the spot of Jared Jones (lat) in the Pirates rotation, which would put him on track to start Sunday against the White Sox. Priester holds a 4.83 ERA across 31.2 innings with the Pirates this season.