WASHINGTON (AP) — The Atlanta Braves started their weekend series in Washington by continuing their winning ways against the Nationals.

By Sunday afternoon, that success meant little to the Braves.

Tanner Roark won his fourth straight start, Denard Span had an RBI double and the Nationals beat Atlanta 4-1 Sunday for a split of the four-game series between NL East rivals.

Atlanta scored one run in dropping the final two games of the series and fell to 1 1/2 games behind the Nationals, which is where they were when the series started.

"You know what, it's funny, baseball is," said Atlanta manager Fredi Gonzalez, whose team is 20-9 against Washington since the start of 2013 and 7-3 this season.

"If we would've lost the first two games and won the last two games you'd be feeling pretty good about yourselves," Valentine said. It didn't happen that way, it happened the other way, so you're not feeling real good about yourself."

Freddie Freeman had two hits for Atlanta. Evan Gattis went 0 for 3 to snap his 20-game hitting streak.

Ervin Santana (5-5) went six innings, giving up three runs and six hits. He walked one and struck out nine.

Atlanta's Chris Johnson was ejected for arguing a checked-swing call in the sixth, and teammate Justin Upton was ejected for arguing after a swinging strikeout in the ninth.

With Washington leading 3-0, the first two Braves reached against Roark (7-4) in the sixth. Manager Matt Williams visited the mound but left Roark in to face Jason Heyward. Roark got Heyward on a fly to right, but Justin Upton singled home Freddie Freeman to make 3-1.

Stammen came on to pitch to Johnson, who attempted to check his swing on a 1-2 pitch. Nationals catcher Sandy Leon appealed the ball call, and first base umpire Tim Welke ruled Johnson had gone around for strike three.

"I had turned around just because I had check swung, to regroup and get myself ready for the next pitch," Johnson said of the play, "and then I heard the crowd start cheering. So I turned around and I was shocked. Shocked that he rung me up on that."

Johnson immediately began yelling and gesturing at Welke and was ejected by home plate umpire Mark Carlson.

"It's a situation where he's a highly competitive guy and he wants to drive those runs in, and he felt like he didn't go around," Gonzalez said.

Stammen retired Andrelton Simmons to end the inning.

Washington relievers retired all 11 batters they faced, and Anthony Rendon made it 4-1 when he doubled in the eighth and later scored on Luis Avilan's wild pitch.

Santana had allowed nine earned runs over 15 innings in his two previous starts.

"Everything was much better today. The location was very good," he said. "First inning was a little bit up, but after that, I was just sort of down and just keep the ball down for the most part."

Roark went 5 1-3 innings, allowing a run and four hits.

"We did a good job of getting Roark's pitch count (up) today," Freeman said. "I feel like we just missed some. I know I just missed a couple . Just a little off the barrel today."

Washington got to Santana in the first, getting and RBI single from LaRoche that deflected off diving shortstop Simmons' glove. Ryan Zimmerman had a sacrifice fly to make it 2-0.

Atlanta threatened in the third. With one out, LaRoche misplayed Freeman's grounder down the first base line for a two-base error. But Roark got Gattis on a grounder to third, and, after Heyward walked, Justin Upton hit into a fielder's choice.

"We had some people on base and just couldn't punch them through," Gonzalez said.

The Nationals made it 3-0 on a Span RBI-double in the fifth.