ATLANTA (AP) -- Gio Gonzalez took off from the mound to cover first base, then stopped before starting to run again.
It was too late.
With first base uncovered, Gonzalez was left to regret his fifth-inning mistake as the Atlanta Braves took the lead in their 3-1 victory over the Washington Nationals on Sunday night.
"I should have gotten over," Gonzalez said. "There's no excuse. You've got to get over on that ball, keep your team in the game."
The mistake helped seal Washington's fate in the game and the series. The Nationals lost two of three, trimming their NL East lead over the Braves to 3 1/2 games.
With the game tied 1-1, Emilio Bonifacio led off the fifth with a bunt single, despite a creative defensive effort by Gonzalez (6-9). The pitcher fielded the ball with his back to first base and flipped the ball between his legs to Adam LaRoche. Bonifacio was safe despite a collision with LaRoche.
With two outs and Bonifacio on third, Jason Heyward hit a grounder to second baseman Danny Espinosa. LaRoche broke for the grounder, leaving first base uncovered as Gonzalez was late running to the bag. Heyward was safe with the single as Bonifacio scored the go-ahead run.
Nationals manager Matt Williams said Gonzalez "got caught watching the play."
"We had a shot at getting (Heyward) at first base, certainly," Williams said. "There was nobody there. Ultimately, that's the difference in the game."
Gonzalez gave up two runs, six hits and four walks in 4 2-3 innings. He has lost four straight starts.
Alex Wood (8-9) set a career high with 12 strikeouts in 7 1-3 innings for the Braves, who are 9-4 against the Nationals this season and 22-10 over the last two years.
"It's almost like a playoff game when we play them, no matter when it is," Wood said. "I think we've got some guys that are gamers in here and really enjoy that challenge and enjoy rising to that occasion."
Justin Upton homered for the Braves, who had lost nine of their last 10.
Ian Desmond's fourth-inning homer was the only run allowed by Wood.
Pinch-hitter Evan Gattis hit a single to right field off Jerry Blevins in the eighth to drive in Chris Johnson, who walked.
Craig Kimbrel, pitching on the third straight night, had a perfect ninth to earn his 34th save.
Denard Span's fifth-inning double to right field gave him a 14-game hitting streak. He also doubled in the seventh and has reached base in 36 consecutive games since June 28 - seven shy of the Nationals' record set by Ryan Zimmerman from April 8 to May 25, 2009.
RESPECT THE A
Braves manager Fredi Gonzalez said he thought the fuss over Bryce Harper scuffing the "A" in the dirt behind home plate with his cleat in Saturday night's game was "silly."
The Braves' official Twitter account posted during Saturday's game: (hash)RespectTheA.
Harper crossed the "A" on Saturday night by walking behind the umpire to the left-handed batter's box. On Sunday night, he took a more direct route to the box by walking in front of catcher Gerald Laird. Even so, Harper was booed by Braves fans before every at-bat. He was 0 for 4.
Nationals: Outfielder Steven Souza, who hurt his shoulder in a collision with the right-field wall Friday, was placed on the 15-day disabled list. Outfielder Michael Taylor was called up from Triple-A Syracuse. ... Werth started in right field after missing two straight starts with a sore right shoulder.
Braves: Gonzalez said shortstop Andrelton Simmons (sprained left ankle) may play Tuesday, take Wednesday off, and then be ready for regular work.
Nationals: Washington is off Monday and right-hander Doug Fister will start in Tuesday night's game at the Mets. Fister will try to extend his successful record - 5-0, 1.80 ERA - when pitching with at least an extra day of rest.
Braves: Right-hander Julio Teheran will face Kevin Correia as the Braves open a four-game series against the Dodgers on Monday night. Teheran took the loss despite allowing only two runs in eight innings at the Dodgers on July 31.
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