This paper reports on the implementation of a Teaching Performance Assessment (TPA), a component of graduation recently introduced into the teaching workforce in Australia. The TPA typically requires graduates to demonstrate that they can plan, implement, assess and reflect on a series of lessons given to school students. This case study used grounded theory to analyse the initial implementation of a TPA at an Australian university, based on interviews, student focus groups, and a classroom readiness survey. We investigated the TPA's contribution to final-year pre-service teachers' learning and professional readiness. We conclude that the TPA, as a threshold task, is broadly beneficial to the profession and graduating teachers, and may strengthen professional bonds between schools and universities. We also warn of TPA-related fragilities and its potential to reinforce populist notions of 'teaching as telling' and to test surface-level quiz-knowledge to the exclusion of deeper, attitudinal learning outcomes.