That brought up Rosario, who raked a hit that rolled to the wall in left field, sending home the key run.
Charlie Blackmon (3-for-4, two RBI) later added an RBI double and Ryan Wheeler capped the uprising with a pinch-hit, two-run single as the Rockies pulled away for a win in the first of a four-game set.
Chad Bettis (1-3) earned the decision for Colorado.
Matt Carpenter and David Freese each provided an RBI for the Cardinals, who remained tied with Pittsburgh atop the National League Central despite the loss.
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