An agricultural baler (10) includes a pre-compression chamber (22) having an outlet (74), and a main bale chamber (26) adapted to receive crop from the pre-compression chamber (22). A plunger (30) is reciprocally disposed within the main bale chamber (26), and includes a plurality of plunger slots (72) which are structured and arranged to allow a plurality of needles (36) to intermittently pass therethrough. The baler (10) is characterized by a plunger cleaner (70, 90, 110, 130, 150) which is structured and arranged to provide the dual functionality of: 1) cleaning the plunger slots (72), and 2) opening and closing the outlet (74) of the pre-compression chamber (22).
