In the second inning, left fielder Ryan Braun threw out Marcell Ozuna trying to turn a double into a triple.
Both plays came against leadoff batters in each inning, thwarting potential rallies.
Domingo Santana's second inning single off the glove of a diving Paul DeJong scored Travis Shaw and snapped the Brewers' 11-inning scoreless streak. Orlando Arcia's two out double scored Santana, giving Milwaukee an early 2-0 lead.
Ozuna redeemed himself in the third with a bases loaded single that scored two, giving the Cardinals a 3-2 lead.
Joe Harris is a contributor to MLB.com and covered the Brewers on Monday