Dustin Ackley, Kendrys Morales, Kyle Seager and Chris Taylor finished with one RBI each as the Mariners won back-to-back games for the first time since winning four in a row from June 29-July 2.
Chris Young (10-6) allowed three runs on seven hits while striking out six in five innings, earning his first 10-win season since 2006 with the San Diego Padres.
Freddie Freeman drove in two of Atlanta's runs with a double in the third inning. He finished 3-for-4 on the day.
Julio Teheran (10-8) struggled for the Braves, allowing six runs on nine hits in his second straight loss.
Atlanta was swept for the third consecutive series and went winless on an eight-game road trip for the first time since 1949.