Washington downed the Mets for the first time in five tries this year, producing 10 runs in a three-inning span. The Nationals won for only the fourth time in 20 games.
The victory went to Michael O'Connor (1-0), who threw one inning in relief of Shawn Hill.
Oliver Perez (2-1) took the loss, coughing up six hits and five runs over 5 2/3. Perez came into the game having not allowed a run in three of his four starts this season.
Washington tied the game with a three-run fifth that featured a two-run single by Lopez.
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