McCullough (forearm) was activated from the 60-day injured list Sunday.
McCullough made four rehab appearances while working his way back from season-ending surgery, posting a 4.26 ERA and 1.11 WHIP with 17 strikeouts over 12.2 innings in two showings in the Arizona Complex League and two with Single-A Myrtle Beach. He was reinstated from the 60-day IL on Sunday and looked strong in his first appearance of the year with Double-A Knoxville later that day, allowing two runs (one earned) on two hits and two walks while striking out four in four frames.