Wainwright (2-1) dominated the Brewers on the mound, striking out 12 without a walk in recording his fifth career shutout on 115 pitches.
He also was potent at the plate, providing RBI singles in the third and sixth innings as St. Louis romped to its fourth straight win and sixth in seven contests.
Milwaukee starter Yovani Gallardo (0-1) was touched for six runs (five earned) on seven hits over 5 1/3 innings.
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