The Dragons scored in the sixth when Jay Allen walked with one out, stole second, and came home with two outs when Rece Hinds lined a double to the left field fence to make it 2-1.
Quad Cities added a run in the bottom of the eighth to extend their lead to 3-1.
Benschoter worked five innings, allowing six hits (five of them in the fourth) and two runs with two walks and five strikeouts. He was charged with the loss.
The Dragons full-season record fell to 55-57 with the loss. They are 16-30 in the second half. Quad Cities improved to 47-68 overall and 21-28 in the second half.