Nolan Arenado hit a 482-foot two-run homer that bounced out of the ballpark in the first inning, Chi Chi Gonzalez got his first big league win in four years and the Rockies beat St. Louis 2-1 on Tuesday night to slow the Cardinals' playoff push.
St. Louis, which had won 23 of 30 coming in, maintained a four-game lead in the NL Central over the second-place Chicago Cubs.
Given the early advantage, Gonzalez (1-6) allowed one run and four hits in six innings.
Jairo Diaz got six outs and finished a six-hitter for second save.
Michael Wacha (6-7) allowed five hits in four innings and is winless in seven starts and two relief appearances since July 19.
Dexter Fowler doubled leading off the fourth and scored on Paul Goldschmidt's groundout.
Dakota Hudson (15-6, 3.40) will face Rockies RHP Antonio Senzatela (8-10, 7.19) in the second of the three-game series on Wednesday. Hudson is 11-2 in his last 14 starts while Senzatela has a 16.15 ERA in his last six outings.