The Cardinals sent 11 men to the plate in the third and scored all their runs in the inning after two were retired. St. Louis won its third in a row.
All the runs in the sixth came against Wily Peralta (2-2), who loaded the bases with two out by hitting Matt Holliday with a pitch.
Mujica, however, struck out Jonathan Lucroy with the tying run on first base to earn his seventh save.
The win went to starter Jake Westbrook (2-1), who allowed a run on six hits in six innings.
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