The present invention provides a method and apparatus for forming an outwardly extending tubular portion in a side wall of a workpiece, such as a rocker arm. The method includes the following steps: (1) positioning the workpiece in a punch press having a central shaft with a movable punch mounted in an aperture formed in the central shaft for lateral sliding movement with respect to the shaft; (b) extending the central shaft into the interior cavity of the workpiece; and (c) actuating lateral sliding movement of the movable punch against the side wall of the workpiece to cold form the outwardly extending tubular portion in the side wall.