Washington, which clinched its eighth winning season in a row, ensured it would not lose ground in the wild card race. The Nationals entered the day as the NL's first wild card, 1½ games ahead of Chicago and 2½ games in front of Milwaukee.
Atlanta's magic number to clinch the NL East remained at four.
Sánchez (9-8) worked seven innings, scattering three hits and a walk while striking out three and not allowing a runner past second base. Coupled with Tuesday's seven innings of two-run ball, it was the first time this season Sánchez pitched more than six innings in consecutive starts.
Sánchez, who signed with the Nationals after spending last season with Atlanta, is 3-0 with a 3.41 ERA in five starts against the Braves. Washington, however, struggled against the division leaders, going 8-11 this season and only winning one series.
Seeking to tie Washington's Stephen Strasburg for the NL lead in victories, Atlanta's Max Fried instead had his shortest outing since May 7. He surrendered two-run singles to Yan Gomes in the second and Kendrick in the fourth. He exited with the bases loaded, and reliever Jeremy Walker immediately walked Victor Robles to force in a run.
Fried (16-6) allowed five runs on six hits and three walks in 2 1/3 innings as the Braves failed to complete their first sweep of the Nationals since 2014 and first sweep in Washington since 2013.
Kendrick added a solo shot off reliever Grant Dayton in the fifth. The 36-year-old has 15 homers on the season, his most since smashing a career-high 18 in 2011.
TRAINER'S ROOM
Braves: INF/OF Charlie Culberson broke multiple facial bones when he was hit by a 91 mph pitch from Washington's Fernando Rodney on Saturday. Culberson was released from a hospital Saturday and was scheduled for additional examinations on Sunday in Atlanta.
Nationals: C Kurt Suzuki (right elbow inflammation), who has not played since Sept. 7, has been swinging a bat but has yet to throw. Manager Dave Martinez said Suzuki will try to hit on the field Monday or Tuesday. ... 1B Matt Adams (AC sprain) remains day to day. Adams has not played since Thursday.
EARLY EXIT
Atlanta OF Matt Joyce was ejected by home plate umpire Bill Welke for arguing a called third strike in the fifth inning. It was his first ejection of the season and fifth of his career.
UP NEXT
Braves: Atlanta has Monday off. The Braves have not announced their starting pitcher for Tuesday's game against Philadelphia, the opener of a six-game homestand.
Nationals: Strasburg (17-6, 3.49 ERA), who is 3-2 with a 2.48 ERA in seven career starts against St. Louis, gets the ball Monday as Washington begins its final trip of the regular season.
