Abstract: Relates to a protective guard or shield for covering the wear area of the moldboard of a plow. The shin member of the plow assembly is provided with an integrally connected rearward extension which overlies the most serious wear area of the moldboard. The shin extension is not bolted or otherwise fastened to the moldboard but relies on a shoulder formed on the back side of the shin for engagement with the leading edge of the moldboard and the provision of a plurality of spaced apart projections on the face of the extension confronting the moldboard for bearing support thereon. The shin and its extension may be used to cover the worn area of a used moldboard or to protect such area of a new moldboard. In the latter case the projections may be ground down to provide surface contact between the shin extension and the moldboard. The shin and its extension are preferably formed of a stainless steel alloy and cast in one piece.