Andrew Cashner (3-2) claimed the victory, yielding three runs on seven hits over 6 2/3 frames. The right-hander issued just one walk and struck out six as San Diego earned a four-game split with the Nationals.
Washington starter Dan Haren (4-5) was lit up for seven runs on nine hits over five full frames.
Ryan Zimmerman clouted a two-run homer and added an RBI single for the Nats.
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