WASHINGTON -- Gio Gonzalez had four subpar starts in a row and had not won at home since July 20 against the New York Mets.

But the veteran left-hander threw six shutout innings and allowed two hits while striking out 10 batters for the first time this season, adding up to an 8-2 win for the Washington Nationals over the Atlanta Braves on Saturday night.

Gonzalez was quick to credit catcher Wilson Ramos.

"Willie did a great job back there mixing it up," said Gonzalez, who took a no-hitter into the sixth inning. "We were trying to pound the strike zone and be aggressive."

Nationals center fielder Bryce Harper had a homer, two doubles and two RBIs to lift his average to .337.

"The guy is amazing. It is incredible to go out there and see him," Gonzalez said. "It is fun to watch."

Gonzalez (10-7) walked four batters before Casey Janssen came on to pitch a scoreless seventh.

"He was effectively wild," Atlanta manager Fredi Gonzalez said of Gio Gonzalez.

It was the 12th time Gonzalez had fanned at least 10 batters in a game.

"It is just being on the same page with Willie," Gonzalez said of his catcher. "Willie wanted to be aggressive today and it worked. The defense was spectacular."

The loss went to Atlanta starter Shelby Miller (5-13), whose ERA rose from 2.56 to 2.86 with some more misfortune in a season of misery. Washington is averaging more than six runs in the last 18 games.

The Nationals (70-65) remained five games behind the first-place New York Mets, who beat the Miami Marlins 7-0 on Saturday. Washington improved to 12-3 this year against the Braves (54-82), who secured a losing season with their 11th loss in a row and 12th straight setback on the road.

"We didn't play very good defense behind him," Fredi Gonzalez said of Miller.

Atlanta has not won a road game since Aug. 2 at Philadelphia and the Nationals, who begin a three-game series at home Monday with the Mets, clinched a fourth series win in the last five. Washington has won four in a row and 12 of its last 18 games.

With an 8-0 lead, Washington manager Matt Williams was able to rest starters Jayson Werth (right fielder) and Yunel Escobar (third base) late in the game.

"He has had a long season. He is grinding," Williams said of Escobar, who has missed time with a few minor injuries.

The Nationals scored four runs in the third against Miller, who has been a hard-luck pitcher all summer.

And it happened again as shortstop Ian Desmond, who led off the third, hit a routine fly that center fielder Cameron Maybin lost in the lights.

Miller retired the next two batters and should have been out of the inning, but Desmond scored on a wild pitch with Werth at the plate.

Werth then hit a ground-rule double and second baseman Anthony Rendon followed with an RBI single. The next batter, Harper, golfed a low outside pitch from Miller over the fence in left-center for a two-run homer and a 4-0 lead.

It was the 500th career hit for Harper, who went deep for the second night in a row and the 33rd time this season.

Washington scored two more runs in the fourth, the first on an RBI fielder's choice by Ramos. On the same play, Desmond scored from second after an error on a throw by Atlanta catcher Christian Bethancourt.

Nationals first baseman Ryan Zimmerman had an RBI single in the fifth to score Harper, who had doubled, to push the margin to 7-0.

Miller, the Atlanta starter, was winless in his previous 19 starts, even though he had a 3.13 ERA during that span. He had lost his previous 11 decisions. On Saturday, he gave up seven runs and seven hits in 4 1/3 innings before reliever Dan Burawa took over in the fifth.

In the seventh, Harper took exception to two strike calls against him by home plate umpire Jerry Meals and then lined his second double of the game to right.

First baseman Ryan Zimmerman, who drove in two runs, followed with an RBI groundout to make it 8-0 against reliever Ross Detwiler, a former Nationals left-hander.

Braves left fielder Nick Swisher (two hits) broke up the shutout with an RBI double in the eighth off reliever Matt Grace, and center fielder Michael Bourn followed with a sacrifice fly to make it 8-2.

Desmond had three hits and Rendon two for the Nationals.

NOTES: Atlanta CF Cameron Maybin left the game in the fourth inning because of a problem with a contact lens. ... Washington RHP Joe Ross (5-5, 3.50 ERA) will start Sunday against Atlanta LHP Manny Banuelos (1-3, 3.33). ... George Lombard, who played with the Braves from 1998 to 2000, was named the minor league field coordinator for Atlanta on Friday. He had been in the Boston Red Sox system as a minor league instructor.