Sandoval's knock with one out nullified the 1-0 lead the D-Backs took in the previous inning on Josh Wilson's solo home run.
The loss went to Arizona closer J.J. Putz (2-1), who blew his fourth save of the season.
Sandy Rosario (1-0) earned his first Major League win by getting the final out of the eighth. Sergio Romo got the save with a perfect ninth inning.
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