Wainwright (8-10) turned in 7 1/3 solid innings and drove in a run with a double in the fifth inning, and drew a bases-loaded walk in the Cardinals' six-run sixth.
Wainwright allowed two runs on seven hits and struck out seven to help give the Cardinals their first win over Los Angeles in their last nine meetings.
Clayton Kershaw (7-6) took the loss, allowing eight runs on seven hits over 5 2/3 innings.
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