A hydraulic tensioner for a traction element drive of an internal combustion engine, is provided having a tensioner housing with a hollow piston located in the housing bore. A check valve is located in the bore along a pressurized fluid path to the hollow piston, and a spring guide located in the housing in proximity to a base of the bore. A tensioning spring extends from the spring guide inside the hollow piston toward the piston head. A pressure relief valve is located within the hollow piston adjacent to the piston head, with the pressure relief valve including a valve body having a flange with a support surface that rests against an inside of the piston head and a hollow spring guide that extends from the flange toward the base of the bore. A valve seat is formed in the hollow spring guide, and a spring is located in the hollow spring guide and biases a valve ball against the valve seat. At least one of the support surface of the flange, the valve seat or the valve ball include surface indentations or irregularities that allow gas venting through the pressure relief valve.