WASHINGTON – Braves rookie Tyrell Jenkins gave up seven runs without making it out of the fifth inning Sunday, and this time there was no thin air as a contributing factor.

There was only muggy, stifling-hot air on a sunny afternoon at Nationals Park, where Jenkins gave up three runs in the first inning and four runs in the fifth of a 9-1 loss that improved the Nationals’ home record to 16-1 against the Braves over the past two seasons.

The Braves lost the last two games of the series after winning Friday’s opener, and finished 5-5 on a three-city trip that included a series win at St. Louis and a four-game split at Milwaukee.

They absorbed a pair of eight-run losses against the Brewers and Nationals in a four-day span, while the Braves’ others four losses this month have been by a combined total of five runs.

“Much needed day off tomorrow,” Braves left fielder Matt Kemp said after his first trip since being traded to the Braves. “Refresh and come back and play some more baseball. Lot of opportunities to win a couple more games than we did, but came up short. We’re playing good baseball since I’ve been here, and we’ve been in almost every game.”

In his seventh major league start, Jenkins (2-3) had his first bad game outside of Coors Field, where he gave up eight hits, seven runs and five walks in 3 1/3 innings of a 7-2 loss to the Rockies on July 24.

On Sunday he allowed six hits, seven runs and three walks in 4 2/3 innings and left after Anthony Rendon’s three-run homer in the fifth pushed the lead to 7-1.

“Between Colorado and the Nationals, probably two of the best lineups I’ve seen,” Jenkins said. “All these guys are major league hitters, you can’t make mistakes and not pay for it. Today I did. I put the team in a big hole that we couldn’t get out of.”

Jenkins walked the leadoff hitter in that inning, a crucial mistake compounded by the fact that leadoff hitter was pitcher Tanner Roark.

“It just kind of happened,” he said. “Obviously I wasn’t trying to walk him. Once that happened it kind of went downhill from there. That can’t happen. It’s something I’ve got to work on.”

Roark (13-6) won his fourth consecutive start and did what he’s done plenty before, handling the Braves without difficulty. In limiting them to five hits and one run in seven innings, he improved to 5-1 with a 1.73 ERA in 14 games (nine starts) against the Braves, including a 1.22 ERA in his past seven starts.

Jenkins’ performance Sunday mirrored the rough outing at Colorado in several aspects. In each game he had a three-run and a four-run inning, and in each case the four-run inning included a three-run homer and multiple walks, both times including a walk issued to the opposing pitcher.

In his first season, Jenkins has totaled more than 40 percent more walks (30) than strikeouts (21) in 46 innings.

“It’s going to hurt you,” Braves interim manager Brian Snitker said. “You can’t go out and give free passes to these guys. It’s a really good offensive ballclub, and you’ve got to make them earn everything they get. You can’t put extra guys on base or it’ll bite you, and it did.”

Before Sunday, Jenkins was 2-0 with a 1.00 ERA and .172 opponents’ average in three starts since the loss at Colorado, allowing 10 hits and two earned runs in that span despite totaling more walks (11) than strikeouts (nine) in 18 innings.

He had fashioned a 1.57 ERA in five starts outside Coors Field before Sunday, when he gave up two more runs than he had yielded in 28 2/3 innings of his previous five starts below mile-high altitude.

The Braves failed to score in the first inning after getting singles from Ender Inciarte and Freddie Freeman to put runners on the corners with one out. Inciarte made a base-running blunder when he took off toward home on Matt Kemp’s comebacker to the mound and was thrown out easily.

The Nationals, on the other hand, didn’t waste their first-inning opportunities. After a leadoff double from Trea Turner, Ben Revere laid down a bunt and catcher Anthony Recker overthrew first base, allowing a run to score and Revere to advance to second.

Bryce Harper, playing for the first time in a week after a neck injury, doubled home the second run, and one out later Rendon’s sacrifice fly pushed the lead to 3-0.

Jenkins only allowed one walk from the second through fourth innings, but in the fifth he got into immediate trouble with the leadoff walk to Roark. Turner followed with a single and one out later Harper walked to load the bases. After a Wilson Ramos sacrifice fly, Rendon hit a home run to the Braves bullpen beyond left field, giving the Nationals a 7-1 lead and sending Jenkins to the showers.