A harvesting machine includes a harvesting header with a header frame, a cutterbar assembly attached to the header frame along the length thereof and configured to cut a crop, and a draper assembly positioned behind the cutterbar assembly. The draper assembly includes a center draper that delivers crop material to a feeder house of the harvesting machine. The center draper includes a draper frame swingably supported on the header frame at a pivot to project forwardly therefrom and a draper belt supported on the draper frame to present a rearwardly moving run for conveying the crop rearwardly. The center draper includes a counterbalance mechanism coupled between the header and draper frames to counteract the weight of the center draper about the pivot.