AP. Pittsburgh’s Oneil Cruz fields a ground hit, which was hit by Arizona’s Alek Thomas during the first inning Monday in Phoenix.

PHOENIX — Zac Gallen pitched seven dominant innings, Ketel Marte had a crucial two-out, two-RBI single in the eighth and the Arizona Diamondbacks beat the Pittsburgh Pirates 3-0 on Monday night.

Gallen (7-2) gave up just three hits and two walks while striking out eight. The seven innings matched a career high he’s reached 13 times in the big leagues. He threw just 89 pitches but manager Torey Lovullo opted to bring in lefty Joe Mantiply for the eighth.

The decision worked. Mantiply retired the Pirates in order in the eighth and Ian Kennedy handled the ninth for his seventh save.

The D-backs scratched out a 1-0 lead in the sixth with some small ball. Geraldo Perdomo reached on an error by Pittsburgh third baseman Michael Chavis before stealing second base. Josh Rojas followed with a bunt single, putting runners at first and third with no outs.

Rookie Alek Thomas then grounded into a double play, but it still scored Perdomo.

The D-backs held that lead with some stellar defense. Rojas made a long throw from third base across the diamond to get the first out of the seventh, then right fielder Daulton Varsho got the second out by throwing out Bryan Reynolds, who was trying to go from first to third on a base hit.

Arizona loaded the bases with no outs in the eighth. The next two batters couldn’t extend the lead, grounding out weakly for force outs at home, but Marte came through, hitting a hard grounder through the right side to push the advantage to 3-0.

Pittsburgh’s Tyler Beede delivered 3 2/3 scoreless innings in his second start of the season. The right-hander gave up two hits, walked one and struck out two. Manny Banuelos (0-1) took the loss, giving up one unearned run over two innings of relief.

TRAINER’S ROOM

D-backs: Placed LHP Kyle Nelson (low back spasms) on the 15 day IL retroactive to Aug. 5. Called up RHP Edwin Uceta from Triple-A to take his spot on the roster.

UP NEXT

The two teams play again on Tuesday night. D-backs LHP Tommy Henry (0-1, 7.20 ERA) will make his second big-league start. The Pirates will counter with RHP Zach Thompson (3-8, 5.15).