South African teacher education policy expects initial teacher education programmes to introduce integrated and applied knowledge to underpin a teacher's practice in diverse classroom contexts. This paper explores how a one-year Postgraduate Certificate in Education responds to this expectation in terms of training prospective teachers to teach high school mathematics. Exploration involves a qualitative case study of semi-structured interviews with six teacher educators and five newly qualified teachers, supplemented with document analysis. The stages of research involved a literature review, piloting the semi-structured interview questions, conducting semi-structured interviews, and analysing all accessible documents linked to the Postgraduate Certificate. All collected data were merged into one document which was read to identify codes, themes and categories. The paper finds that the Postgraduate Certificate does equip individuals with professional teacher knowledge to function in diverse contexts, albeit unevenly and highly dependent on the quality of each teacher's past engagement with mathematics. The broad nature of policy knowledge type definitions and the lack of clarity in differentiating 'specific specialised subject matter' and 'specialised pedagogical content knowledge' are key contributing factors to uneven development in a Postgraduate Certificate. As a recommendation, we suggest that policy should differentiate 'specific specialised subject matter' and 'specialised pedagogical content knowledge' in more detail to promote the development of each as important types of knowledge needed by teachers.