Matt Wieters homered, Bryce Harper added an RBI double, and starter Tanner Roark allowed just one run over seven innings as the Washington Nationals defeated the Cincinnati Reds 2-1 on Sunday afternoon at Nationals Park in the finale of a four-game weekend series.

The Nationals, who had been struggling before last week, took three of four in the series. Washington has won five of its past six games while trying to stay in the hunt for a postseason berth.

Roark (6-12) continued his recent turnaround with a third consecutive strong start. He gave up seven hits and no walks while striking out two to win for the third straight time. The right-hander has allowed just two runs in 22 innings in that span, which has come at the right time for the Washington rotation.

Ryan Madson came on and took care of the eighth inning, striking out two in a perfect inning.

Kelvin Herrera closed it in the ninth for Washington, earning his 17th save overall this season, his third as a National. He needed 29 pitches to get through the ninth inning in a non-save situation in Saturday night's win but retired the side in order on just 12 pitches this time.

Cincinnati starter Luis Castillo (6-9) lost for the first time since June 16 after going 2-0 with five no-decisions in his previous seven starts. He gave up two runs on six hits in 5 1/3 innings and lost to the Nationals for the second time this season.

Wieters gave the Nationals a 1-0 lead with a two-out homer in the bottom of the second inning. It was just his fourth home run this season, as the Washington catcher missed nearly two months after undergoing hamstring surgery in mid-May.

Harper, back in the lineup after coming out of Saturday night's game when he got hit in the knee with a pitch, made it 2-0 with an RBI double off Castillo in the third.

The Reds cut it 2-1 in the fourth on a Mason Williams RBI single. Cincinnati began that inning with four consecutive hits, and the Williams single left the bases loaded with no outs. However, Roark escaped that jam by retiring the next three batters, holding onto the 2-1 lead. Neither team scored again.

--Field Level Media