Schneider smacked a drive over the centerfield wall in the fifth-inning, putting the Mets ahead 4-0. Delgado hit a solo homer in the sixth and finished with two RBI in the Mets' sixth win in eight games.
Winner Oliver Perez struck out eight Nationals in 6 2/3 innings. Perez allowed three runs and six hits.
Pete Orr hit a two-run triple for Washington.
Collin Balester (2-5) took the loss, surrendering five runs over six innings.