WASHINGTON — Slumping Bryce Harper was moved to the leadoff spot for the first time since 2013 and responded with a three-run homer that helped Max Scherzer win his fifth straight start as the Washington Nationals beat the Pittsburgh Pirates 12-4 Wednesday night.

Harper entered in a 5-for-35 slump and had not gotten an extra-base hit since April 16. He grounded out in the first inning against Chad Kuhl (3-2), followed Wilmer Difo’s go-ahead homer in the third with a flyout, then gave the Nationals a 5-0 lead in the fifth with his ninth homer this season.

Harper walked for the major league-leading 39th time this season in the sixth, then left the game with Washington up 12-0.

“Last night I spoke to Harp and I just came to the conclusion: `Why not?”’ Washington manager Dave Martinez said before the game. “He’s a little frustrated and, hopefully, he gets some more pitches to hit.”

Harper raised his batting average to .250. The home run was the fifth of his career from the leadoff slot.

Scherzer (6-1) allowed two runs and three hits in 6 1/3 innings, striking out eight and walked one as his ERA rose slightly to 1.79.

Corey Dickerson hit a two-run homer off Scherzer in the seventh, and Max Moroff hit a two-run drive against Carlos Torres in the ninth.

Ex-Slippery Rock University star Matt Adams hit two solo home runs for Washington.