Fielder's run-scoring groundout and Dirks' RBI single in the sixth helped turn back a New York rally after the Yankees had narrowed their deficit to 5-4.
Max Scherzer (1-0) struck out seven over five innings to earn the victory. The right-hander yielded four runs on five hits while walking two.
Yankees starter Phil Hughes (0-1) allowed four runs (three earned) on eight hits over four full frames.
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