This paper critically examines the tensions arising between Reception teachers' professional beliefs and knowledge, and the school readiness agenda in England. It scrutinises how the increasing academic expectations placed on children to ensure they are 'ready for school' may conflict with teachers' understanding of how young children learn, their pedagogical philosophies and classroom practices. In this paper, cultural-historical activity theory (CHAT) is utilised as a methodological and analytical framework, specifically harnessing Engeström and Sannino's work on 'manifestations of contradictions'. This theoretical lens is applied to elucidate the specific contradictions that surface at the policy-practice interface and to explore how teachers navigate these conflicts and tensions. Data were gathered through interviews with two Reception teachers and analysed to identify four distinct contradiction categories: dilemmas, double binds, critical conflicts and conflicts. The findings make a critical contribution to ongoing debates about the implications of the school readiness agenda on teacher beliefs, professional knowledge and the impact on children. Furthermore, this paper extends an original contribution to the practical application of CHAT in Early Childhood Education (ECE) research and emphasises the utility of identifying linguistic cues as an effective strategy to reveal contradictions in textual data, thereby furthering understanding of policy--practice tensions in ECE.