Volstad (1-9), who last won a game July 10, 2011, as a member of the Florida Marlins, scattered three hits and three walks, while striking out three in a contest delayed twice by rain before being called after eight frames.
Manny Corpas extricated Chicago from a two-on, two-out jam in the seventh and Shawn Camp pitched a scoreless eighth for his second save as the Cubs took two of three from Colorado.
The loss was hung on Colorado's Jhoulys Chacin (1-4), who yielded only one run on five hits over five frames.
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