PHOENIX (AP) — The Arizona Diamondbacks activated ace Zac Gallen from the injured list to start Saturday’s game against the Oakland Athletics.

The right-hander (5-4, 3.12 ERA) left his previous outing on May 30 at the New York Mets after facing one batter. He was diagnosed with a right hamstring strain and was placed on the injured list.

Last season, Gallen was 17-9 with a 3.47 ERA in leading the Diamondbacks to the World Series. He was the starting pitcher for the National League in the 2023 All-Star Game.

The 28-year-old is 44-35 in his career with a 3.20 ERA. Gallen led the NL in 2022 in fewest walks and hits per innings pitched (0.91).

To make room on the roster, Arizona optioned left-hander Brandon Hughes to Triple-A Reno. Hughes had a 10.29 ERA in 14 innings for the Diamondbacks. He gave up eight home runs, including three in one inning Friday against the A’s.