The Braves, who snapped a five-game losing streak, began the day 5 ½ games behind Pittsburgh for the second NL wild card.
Steven Souza Jr. hit his first career homer for the Nationals. Washington manager Matt Williams gave his regulars a day off one day after the Nationals clinched the NL East title.
Alex Wood (11-10) allowed one run on five hits with eight strikeouts in six innings. Craig Kimbrel pitched a perfect ninth for his 44th save, his first since Sept. 6.