Along with any other defenses he may have in an action of ejectment or in an action in the nature of ejectment, the defendant may disclaim possession of the premises sued for in whole or in part. If the defendant pleads the defense of disclaimer only and no other, the plaintiff may take judgment or may take issue; and, if the issue is found for him, he is entitled to judgment as if the defendant had, in an action of ejectment, entered into the consent rule, confessing possession as well as lease, entry, and ouster or, in an action in the nature of an action of ejectment, had admitted possession.