WASHINGTON -- As reliever Amir Garrett began serving the first game of an eight-game suspension on Monday, Reds starter Anthony DeSclafani did exactly what his team’s shorthanded bullpen could have done without.

Not only did DeSclafani labor on the mound, his start lasted just four innings during the Reds’ 7-6 loss to the Nationals. It was another hit to Cincinnati’s fledgling postseason hopes as the club dropped to six games behind the National League Wild Card-leading Nationals and 7 1/2 games back of the idle first-place Cubs in the NL Central.

“The whole game was frustrating,” DeSclafani said.

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DeSclafani tied a season high with six earned runs allowed, something he hadn’t done since June 23. His 83-pitch, four-inning start was his shortest since he worked 3 2/3 innings on May 24. He came in 5-3 with a 3.49 ERA over his previous 11 starts.

Things opened optimistically in the first inning for the Reds when leadoff batter Jesse Winker attacked Erick Fedde’s very first pitch for an opposite-field home run. The one-run lead disappeared quickly in the bottom of the first.

Not putting away hitters would prove to be DeSclafani’s undoing.

One strike away from ending the first inning, DeSclafani had Matt Adams in a 1-2 count before a fastball missed high. His 2-2 slider to Adams was lifted to center field for a two-run homer. Asdrubal Cabrera followed with a double to right-center field that was nearly caught by a diving Nick Senzel. Gerardo Parra made it a 3-1 game with his RBI single to center.

More two-out Washington hits doomed DeSclafani in the bottom of the fourth inning. After Victor Robles’ single, DeSclafani again had two strikes when Fedde blooped a single to right field. On a 3-2 pitch to the next batter, Trea Turner, DeSclafani gave up a three-run homer to left field. Turner was initially down, 0-2.

“Just throw a slider away,” DeSclafani said of his plan with Turner in the full count. “If I was going to miss, obviously, it was going to be a slider down, off. But it ended up just being a spinner in the middle of the zone.”

DeSclafani has given up 24 home runs this season, but 10 of them have been when runners are on base -- including four of the last five.

“The solo homers are easier to work around. I know he believes he’ll get back on track,” Reds manager David Bell said. “We’ll be able to help him do that. I know he’s not right where he wants to be right now, but it wasn’t too long ago that we were talking about him having three or four or five good ones in a row, too. He has something to go back to.”

DeSclafani had been developing a stronger curveball earlier in the season, but he didn’t have much faith in it on Monday. He only threw a curve seven times, getting one swing-and-miss.

“I’ve only got two pitches, so if my slider doesn’t have depth that day or I’m not elevating within the zone where they are going to attempt, it’s going to be tough to strike guys out,” DeSclafani said. “That’s what I kind of felt today. They didn’t have anything to cover, really. Everything was hard and nothing really with depth. It just made it difficult.”

Over the final four innings, Washington added just one more run in the seventh against Jared Hughes. Kevin Gausman worked a scoreless fifth and sixth on 32 pitches, while Hughes needed 45 pitches to get through the seventh and eighth.

It enabled the Reds to make it a tight game with a two-run home run from Aristides Aquino in the eighth inning and a pinch-hit solo homer from Phillip Ervin in the ninth.

“Overall, given the circumstances, [the bullpen is] in pretty good shape,” Bell said. “That’s because of the job Gausman and Jared Hughes did. Only allowing one run over four innings kept us in the game. Also, they took those innings on so we didn’t have to use anyone else.”

Votto thrown out at the plate

After Winker’s homer in the first inning, Fedde walked the next batter, Joey Votto. Eugenio Suarez’s groundout moved Votto to second base and potentially set the stage for a bigger inning.

When Josh VanMeter rolled a single into center field, Victor Robles charged the ball and scooped it up in a hurry. Third base coach J.R. House waved the slow-footed Votto around, but Robles’ throw to the plate easily cut down Votto by several feet before he slid into the plate unsuccessfully. VanMeter went to second base on the throw, but the rally died when Aquino struck out.

“I think in that situation, if J.R. had to do it over again, he wouldn’t have sent him,” Bell said. “But absolutely we love the aggressive base running. On the other side of that, J.R. has done an unbelievable job at third base this year and scored a lot of guys. So we want him to stay aggressive, too.”

Robles has a good arm and it showed as Statcast tracked his throw at 99.5 mph from 220 feet. It was the fourth-fastest throw of the season among Major League outfield assists.

“For every third-base coach, there are going to be times where you get guys thrown out,” Bell added. “It’s really a lot tougher job than people realize. [House has] been outstanding over there all year.”