The win went to Sean Gallagher (2-0), who had given up Helton's dinger.
The home run fest also included a three-run shot by Chris Snyder and a solo blast by Garrett Jones, who helped the Pirates win for the third time in five games.
Miguel Olivo and Troy Tulowitzki also drove in runs for the Rockies, who have lost three of five.
The loss and blown save went to Huston Street (2-3), who was charged with all three Pittsburgh runs in the 10th.
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