The Braves (50-83) no longer have the majors' worst record. Minnesota (49-84) fell below Atlanta with its 13th straight loss, 8-4 to Cleveland. The Twins and Braves began the day tied in the race for the No. 1 pick in next year's draft.
Wisler (6-11) allowed one run on only four hits in his third straight win. His last strikeout against Derek Norris ended the sixth with runners on first and second.
The Braves led only 2-1 before Beckham's two-run double off Kevin Quackenbush. Ender Inciarte added a two-run single in the four-run inning.
Paul Clemens (2-4) was hurt by four walks as he allowed two runs, one earned, in three-plus innings.