Atlanta pulled within three games of NL wild card-leading Colorado, which was scheduled to play St. Louis later in the day.
The Braves (84-70) have won 13 of 15 and are 50-30 since June 27, improving to a season-best 14 games over .500.
Hanson (11-4) allowed four hits and four runs _ three of them on Mike Morse's pinch-hit homer. The impressive rookie, who made his major league debut on June 7, struck out seven and walked one.
The Braves took advantage of Washington's shoddy defense to jump out to a 5-0 lead. Escobar had a two-out, two-run single off Garrett Mock (3-10) in the first and third baseman Pete Orr's throwing error on Matt Diaz's slow roller led to two more runs.
Orr got the start in place of Ryan Zimmerman, who pinch hit in the eighth inning and flied out.
Right fielder Elijah Dukes committed the first of his two errors in the second, muffing Chipper Jones' fly ball for a two-base miscue that allowed Martin Prado to score. Dukes also committed an error in the ninth.
Washington, which has eight games left and matched its total from last year with its 102nd loss, has allowed five unearned runs on four errors in the last two games.
Atlanta broke it open with five runs in the ninth. Brian McCann hit a two-run homer, Jones and Escobar had RBI doubles and Adam LaRoche singled in a run.
Mock, who lost his fifth consecutive decision, allowed six runs, four earned, and seven hits in five innings. Willie Harris had a two-out RBI single in the third, Morse connected in the fifth and Ian Desmond added a sacrifice fly in the ninth for Washington.
NOTES: Nationals manager Jim Riggleman said Zimmerman is a little banged up. ``He's been playing through some nagging stuff,'' Riggleman said. ``He's sore in a couple of different areas.” Zimmerman expects to play Sunday. ``I think everyone is banged up right now,'' he said. ... Nationals SS Cristian Guzman may not play in the field again this season. He's suffering from a sore
shoulder, which has limited him to pinch hitting. ... Nationals LHP Sean Burnett, whose bruised left thumb has hampered him, may not pitch again this season. ``I doubt if we'll use him. That bone contusion has not gotten better,'' Riggleman said. ... Atlanta is 45-35 on the road and 39-35 at Turner Field. ... The Braves are the only NL team without a grand slam.