
Greinke (12-2, 1.65 ERA) gave up six hits and walked one, striking out six, in six innings of work.
Puig hit a two-run homer in the fourth off Joe Ross (3-4, 3.44 ERA), then chased Ross in the fifth with a two-out, three-run triple.
Washington (58-54) is two and a half games back of the New York Mets in the National League East.