This study, located in a School of Education in South Africa, explores English Education pre-service teachers' perceptions of preparedness to teach grammar and the influences that shape such perceptions. To understand the knowledge gap in English Education pre-service teachers' readiness to teach grammar, the study employed an interpretive paradigm, qualitative approach, case study design and purposive sampling. Data was generated using open-ended questionnaires and semi-structured interviews. Findings from the study revealed that the pre-service teachers of English believed that they were not ready to teach grammar upon graduation and their lack of preparedness was attributed to their prior negative experiences of learning grammar at school and on the focus of their teacher education programmes on pedagogical knowledge and not content knowledge. This paper argues that the knowledge gap between the thought and taught knowledge need to be addressed to enable pre-service teachers to leave teacher education programmes with confidence.