Nolan Arenado homered for the second game in a row and Happ combined with four other hurlers on a five-hit shutout.
St. Louis has won four of six.
Giovanny Gallegos finished, picking up his eighth save in 15 opportunities.
RHP Dakota Hudson continued his rehab stint with a start Sunday night for Double-A Springfield. He has not allowed an earned run in three previous minor league starts covering 8 2/3 innings.
RHP Adam Wainwright (15-7, 2.98) will face New York Mets LHP Rich Hill (6-6, 3.82) on Monday in the first of a three game series in New York, 5:15 with the pregame and the first pitch at 6:10 on KIRX.