AP Sports Writer
WASHINGTON (AP) -- The Washington Nationals led the Atlanta Braves 4-0 after two innings. The margin was 4-1 entering the eighth. And 4-2 into the ninth.
That all disappeared, thanks to a shaky bullpen and a mistake on defense.
Atlanta reserve Ramiro Pena hit a two-run homer off Craig Stammen with two outs in the 10th inning, and the Braves stretched their winning streak to seven games by coming back to beat NL East rival Washington 6-4 Friday night.
Nationals left-hander Ross Detwiler has two no-decisions despite a 0.69 ERA this season, because relievers gave up leads in both of his starts.
"We need to do better," said Tyler Clippard, who replaced Detwiler to begin the eighth. "Ross pitched a (terrific) game. It hurts. It hurts, obviously, for the club to get the loss. But it hurts for him. ... To have your starter do what he did and not get the win for him is very, very disappointing for us as a group."
Pena, cut by the New York Yankees last September, reached on a bunt as a pinch hitter in the eighth, when the Braves scored once. They added two in the ninth and another two in the 10th. His homer was his first this season and the third of his five-year career.
He said he was looking for one thing from Stammen (2-1).
A fastball down the middle.
And he got one.
"I was just going to concentrate on one pitch, and he threw it right there," Pena said, "and good thing I didn't miss."
Eric O'Flaherty (2-0) pitched a 1-2-3 ninth for the win, while Craig Kimbrel retired the heart of Washington's order for his fifth save in five chances.
"We know the game's not over until we're back in the clubhouse," said Chris Johnson, whose seventh-inning homer off Detwiler began Atlanta's rally from a four-run deficit. "I think there's a deep part of everybody that thinks we are going to come back every time it happens, so it's a good feeling."
The Braves, a major league-leading 9-1, handed Washington its first loss in seven home games.
Atlanta tied the game in the ninth, when Washington third baseman Ryan Zimmerman's throwing error contributed to reliever Drew Storen blowing a save. It was Storen's first save chance since giving away a ninth-inning lead against the St. Louis Cardinals in Game 5 of an NL division series last season.
On Friday, Nationals manager Davey Johnson wanted to stay away from new closer Rafael Soriano, who had pitched each of the previous three days, earning three saves during a sweep of the Chicago White Sox.
Clippard got two quick outs in the eighth before everything started to unravel.
He went walk, single, walk, walk -- with that last pass to B.J. Upton forcing in a run to make it 4-2.
"The execution wasn't there. My changeup was nonexistent tonight," Clippard said. "I wasn't able to put that where I want to, and that hasn't happened in a long time."
On came Storen. He got the third out of the eighth on a fly ball to the warning track in center by 26-year-old rookie Evan Gattis.
Then, in the ninth, consecutive singles off Storen put two runners on, and a sacrifice bunt pushed them to second and third. With two outs, Storen walked Jason Heyward to load the bases for Justin Upton, B.J.'s brother.
Justin Upton hit a hard shot to Zimmerman, who tried to throw to second for a forceout that would have ended the game. But Zimmerman's throw was wide of the bag and sailed into right field. Justin Upton was credited with a single and one RBI, while the second run that scored on the play was unearned because of Zimmerman's throwing error. That made it 4-all.
"Tough play. I think, obviously, first base is out of the question. I'm not going to beat the guy to third. I thought if I turn and make a perfect throw, I had a chance to get the guy bang-bang at second," Zimmerman explained.
"We definitely need to learn from our mistakes," he added. "It's the same thing that kind of got us last year, and why we didn't maybe move on, because we couldn't close games out both pitching and defense-wise."
NOTES: Zimmerman played in his 1,000th game with the Nationals. ... Bryce Harper hit his fifth homer of the season in the first inning against Julio Teheran.
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