Walston (elbow) paused his rehab program earlier in the season, but he was expected to start building back up around the middle of May, MLB.com reports.
Arizona hasn't provided any concrete information regarding where Walston currently stands in the rehab process, but he's not expected to be a realistic candidate to return from the 60-day injured list until after the All-Star break. The 24-year-old left-hander hasn't made an appearance in an official game since spring training of last year after undergoing Tommy John surgery March 26, 2025.