Gio Gonzalez coasted to the victory by going the distance and winning for the 17th time this season.
Gonzalez (17-7) won for the fourth time in five starts. He allowed five hits and struck out eight in recording the first shutout of his five-year career.
Adam Wainwright (13-11) took the loss, giving up the first six runs on nine hits in just 2 1/3 innings.
The Nationals have won three in a row after losing five straight to equal their longest skid of the season.
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