Soriano became the fourth player in major league history with 40 home runs and 40 stolen bases in the same season, after a steal in the first inning against Milwaukee.
Pedro Astacio (4-5) picked up the win, giving up four runs and six hits through 5 2/3 innings for the Nationals, who had lost six of their last eight games.
Bush (11-11) suffered the loss, yielding five runs on seven hits in four innings.
Soriano's game jersey was shipped to the Hall of Fame after the game.
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