Much of the current transitions-based research literature has investigated 'end points' (i.e., coming away from sport and the retirement stage) and not 'within transitions' (i.e., what happens more frequently whilst in the sport). More definitively in relation to football, there has tended to be a specific research focus on younger age groups such as academy players and academy environments. There is limited research which involves professional players and professional cultures. This has been largely in part due to the difficult nature of research access and confidentiality issues around professional sport. Therefore, the present thesis has extended knowledge of transitions by moving the research field into professional sport (football) and professional football culture. As well as the 'end points' of transition the thesis has investigated experiences that professional football players had more frequently and how these experiences threatened, disrupted and challenged identity. Across three studies utilising a pragmatic research philosophy, the thesis explored transitions, critical moments, athletic identity, and the culture of operating in a first team professional football environment. Study One used an evocative, analytic auto-ethnography which provided a rich, detailed account of personally lived experiences of the author. These experiences were charted around different transitional points spanning approximately 20 years in total and written using a monological narrative approach. Key moments were highlighted using a showing, not a telling approach. The narrative presented a range of issues within the journey of a professional footballer.