The Diamondbacks announced Tuesday that they’ve activated right-hander Zac Gallen from the 10-day injured list. Righty Matt Peacock was optioned to their alternate site in order to open a spot on the active roster. Gallen was diagnosed with a hairline fracture in his right forearm last month — an injury he sustained while taking batting practice late in camp. Assuming there are no setbacks, it seems Gallen’s injury will only cost him a couple weeks of regular-season action.

Gallen, 25, will return to a D-backs rotation that has struggled thus far in 2021, thanks largely to uncharacteristically rough showings from Madison Bumgarner and Merrill Kelly. Bumgarner has been hammered for 17 runs in just 13 2/3 innings — walking eight of the 73 batters he’s faced (10.9 percent) and plunking another three. Kelly, who is trying to work his way back from thoracic outlet surgery that ended an excellent 2020 campaign prematurely, has surrendered nine earned runs in 10 frames.

Gallen will take the place of Riley Smith in the team’s rotation, manager Torey Lovullo tells reporters (Twitter link via’s Steve Gilbert). If he’s back to full strength, he should step in as the team’s top starter. Already traded twice in his young career, Gallen landed with the D-backs in the 2019 deadline swap that sent Jazz Chisholm to Miami. The move was a surprise at the time, given Gallen’s six years of remaining club control and his hot start to his rookie campaign that year. He’s been every bit as good in 115 2/3 innings with the Snakes as he was in 36 1/3 frames with the Fish, pitching to a combined 2.80 ERA with a 28.5 percent strikeout rate and a 9.1 percent walk rate following the trade.