This article outlines how a cyclic process of reflection and action was strengthened by the role of an external critical friend in a collaborative self-study. As three teacher education practitioners, two of us participated in the collaborative self-study, acting as internal critical friends to each other, while the third added an external layer of criticality. We both coached the university football team through one playing season: planning, coaching and reflecting collaboratively. Examination of the collaborative self-study identified two essential elements that supported our learning. The collaborative self-study was supported by a cyclic process of reflection, planning and action, and this foundational layer with review and deliberation to support the critical reflection contributed to learning and practices, both as coaches and as teacher education practitioners. A second layer of collaboration, in conjunction with an external critical friend, added to the depth of critique. While the role of critical friend is not new to self-study, analysis of data from both layers of critical friendships is useful in exploiting the structures and methods used throughout the study to contribute to individual and collaborative learning. This article presents the intricate details of the modus operandi -- the repetitive cycle of action and reflection at the foundational layer, and the additional review and deliberation with an external critical friend in the second layer.