The general aim of this study is to clarify whether Maurice Merleau-Ponty's radical reflection offers an adequate foundation for sport embodiment. It is thus necessary to develop a thorough-going description of ”radical reflection” as a key method used by Merleau-Ponty and then draw primarily on the description to present guiding clues for a radical reflection grounded theory of sport embodiment. In order to pin down what Merleau-Ponty really meant about the nature of radical reflection, this study draws the triangular relationship among radical reflection as a method, a philosophy and an existential practice all together. Throughout the disclosure of the triangular relationship, radical reflection can thus deepen the study of sport embodiment and hence sport ontology.