An agricultural baler comprising a main bale chamber having a pair of opposed side walls. Each side wall includes a plunger slot arrangement defining a plunger slot. Each plunger slot has opposite ends and is open at both an inside adjacent to a plunger and an opposite outside. The plunger is reciprocally disposed within the main bale chamber, and includes a pair of opposed sides and at least one roller extending laterally outward from each side. Each roller is positioned within a respective plunger slot. The baler is characterized by a pair of plunger slot covers, with each cover only partially covering a respective outside of a corresponding plunger slot such that each end of the plunger slot is uncovered.
