An accessory for preventing a pre-hung door from sagging in a door frame comprised of a retainer for supporting one side of the door on a lock jamb of the frame and a bolt which is slideable in the frame for preventing the door from rotating in the frame. The retainer has a “U” shaped portion which receives a lock jamb and an adjoining cylindrical portion which engages a bore in a door. The bolt is an elongated slender member having an enlarged end portion which engages a pocket in the lock jamb and a spur which resists a withdrawal of the bolt from the lock jamb.