This study explored the role teacher education plays in influencing student teachers' pedagogical grammar cognitions--defined as what student teachers know, think, and believe regarding grammar instruction--on the premise that investigating the impact of teacher education (or lack thereof) is more fruitful when considering it the result of complex interactions between various teacher education influences (and prior cognitions) rather than the outcome of individual courses. An instrumental case study was conducted to examine how a TEFL (teaching English as a foreign language) bachelor degree program in the Netherlands attempted to impact student teacher cognitions on grammar instruction. For this purpose, various groups of stakeholders (16 student teachers, 10 teacher educators, and 6 school placement mentors) were interviewed, 30 hours of teaching were observed, and multiple data sources were triangulated. The outcomes demonstrate how several manifestations of "incongruence," in secondary education as well as in teaching practice, fostered instead of challenged student teachers' traditional pedagogical grammar cognitions, which were further consolidated and reinforced--albeit unintentionally--in teacher education as a result of inconsistencies in the curriculum, incongruent teaching models, and confusion arising from the dichotomy between disciplinary knowledge and pedagogical content knowledge.