Ovarian tumor is the most common diagnosis in postmenopausal women, presenting with a pelvic mass, though other surgical causes can still be a remote possibility. We report an extremely rare case of a woman, post hysterectomy, presenting with a pelvic mass where both clinical and radiological evaluations were suggestive of an ovarian tumor. The patient underwent laparotomy and a pre-sacral cystic mass was found and excised. Histopathology revealed a schwannoma as the final diagnosis. Hence, it mandates a high index of suspicion to consider other surgical possibilities, vigilant management in the form of advanced radiological evaluation, especially when dealing with doubtful cases of adnexal tumors prior to surgery.