Abstract: A supporting assembly providing lateral support for the nib of a punch in a power press having a stripper plate to prevent breaking of the punch when punching thick workpieces. The bushing which conducts the nib of the punch through the stripper plate has a coaxial annular recess in its underside. An annular insert of resilient polymeric material, preferably polyurethane plastic, completely fills the recess and presents an inwardly-directed collar surface substantially aligned with the opening in the bushing. The insert is dimensioned to project downwardly a short distance beyond the punch bushing to provide an exposed striking surface for engaging the workpiece as the ram descends. The reaction force of the springs on the stripper plate is sufficient to volumetrically deform the insert causing the inwardly directed collar surface to crowd against the nib of the punch, thereby providing enhanced lateral support for the punch as the punch penetrates the workpiece.