The only run off Sanchez (3-3) came in the fifth inning following catcher John Buck's throwing error. Otherwise, the Marlins right-hander handled the Nationals on three hits, issuing only one walk while striking out five.
Randy Choate and Steve Cishek combined to hold Washington scoreless in the eighth despite issuing a hit and two walks, while Heath Bell racked up his ninth save as the Marlins clinched their three-game home series.
Edwin Jackson (1-3) absorbed the loss, yielding a pair of runs (one earned) on five hits over 6 2/3 innings for the National League East-leading Nationals.
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