AP Sports Writer
WASHINGTON (AP) -- Jason Heyward singled and Justin Upton doubled in a three-run eighth inning Wednesday night in the Atlanta Braves' sweep-capping 6-3 win over the Washington Nationals, a game played nicely by both sides one night after a fastball to Bryce Harper's thigh cleared both benches.
Upton also homered, and Kris Medlen (9-10) allowed three runs and three hits over seven innings as the Braves won their 13th straight to take a staggering-for-early-August 15½-game lead over the second-place Nationals in the NL East. While Atlanta has a ways to go before it can mathematically clinch, the three-game dismissal of Washington was undoubtedly a psychological clincher that only could be undone by a monumental collapse.
The Braves rallied off relievers Ryan Mattheus (0-1) and Ian Krol with two outs in the eighth as the Nationals lost their fourth straight and sixth of their last eight. The defending division champs scored only six runs in the three games and are losing hope for an alternate path to the postseason as well, falling nine games off the wild card pace.
Craig Kimbrel pitched the ninth for his 36th save, working out of a jam after allowing a double to Harper and a walk to Jayson Werth with none out. He struck out Adam LaRoche and Ian Desmond, then walked Anthony Rendon before getting Wilson Ramos to line out to right.
In addition to the Braves' chance to effectively bury the Nationals, the game had an extra edge of anticipation following Tuesday's antics involving Harper, Julio Teheran and the teams' Twitter feeds.
Harper took exception when he was drilled by Teheran after homering off the Atlanta starter in his previous at-bat. The implication was that the Braves were upset that Harper trotted around the bases at a slower pace than his usual sprint.
Both benches emptied, but no punches were thrown. Shortly afterward, "Clown move bro" was posted to the Braves' official Twitter account -- a spinoff of Harper's famous line: "That's a clown question, bro." The Nationals responded by tweeting: "Which part, giving up the home run, or drilling the 20-year-old on the first pitch his next time up?"
Braves general manager Frank Wren said before Wednesday's game the tweet directed at Harper was "an inappropriate attempt at humor." When asked about any possible retaliation, Nationals manager Davey Johnson said it would be "just baseball as usual" before flashing a smile.
While the game passed without incident -- Harper went 1 for 3 with a walk and a double, and no one was hit by a pitch -- the saga might not be over. The teams play six more times this season, including a three-game series next week in Atlanta.
Nationals starter Jordan Zimmerman labored through four innings yet allowed only two runs. His biggest pitch was his last one -- a slider that struck out Freddie Freeman with the bases loaded and two out in the fourth.
Medlen, meanwhile, didn't allow a baserunner until the fourth inning, when he walked Harper with two outs. Werth followed with a two-run homer to tie the game.
Upton lined a homer to the bullpen beyond left field in the seventh off reliever Fernando Abad to give the Braves a 3-2 lead, but the Nationals tied it in the bottom of the inning when Werth singled and scored on Desmond's groundout.
Andrelton Simmons started the rally in the eighth with a two-out double off Mattheus. After a walk to a pinch hitter, Heyward singled in a run off Krol. Upton followed with a two-run double to the left-field corner
Notes: Braves CF B.J. Upton has his first four-hit game of the season to raise his average to a season-high .198. ... Nationals RHP Tanner Roark made his major league debut with two scoreless innings. He also made a superb defensive play, diving to catch Medlen's sacrifice bunt attempt and throwing to first for a double play. ... Heyward returned to the lineup after leaving Tuesday's game with a strained neck muscle. "I felt a lot better when I woke up," he said. "Didn't have any head weirdness or headache or anything like that."
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