Purpose: This study examined the relationship between early career teachers' (ECTs') perceived professional competence (PC) and teacher buoyancy (TB) and the contribution of such dynamic interaction between ECTs' perceived PC and TB to their thriving in the face of everyday teaching challenges. Design/methodology/approach: The study adopted a concurrent mixed-methods research design. A total of 218 ECTs taking a postgraduate, part-time initial teacher education programme completed two quantitative measures: Professional Competence Questionnaire and Teacher Buoyancy Scale -- Extended Version. Structural Equation Modelling (SEM) analysis was conducted to examine the relationship between PC and TB. Qualitative data via semi-structured interviews were collected from 14 survey respondents and were interpreted through a case study approach. Findings: The quantitative findings showed--(1) Competence in classroom teaching predicts the personal and contextual dimensions of teacher buoyancy; and (2) Competence to work in schools predicts the personal dimension of teacher buoyancy. The qualitative findings showed two cases that exemplified how the dynamic interaction between ECTs' perceived PC and the personal and contextual dimensions of TB supported their development of teaching expertise. Originality/value: The paper provides empirical findings on the relationship between PC and TB. It highlights ECTs' perceived Competence to work in schools as goal alignment and engagement with school policy as a crucial facilitating condition that develops ECTs' capacity to face daily challenges and engenders their thriving in terms of development of teaching expertise.