The aim of this paper is to describe the process of legitimatization of a public space through the process of management and utilization at the Tarumi-ku danchi in Kobe city. The danchi residents who had used the areas continuously for sport were assigned as agents for managing the public space. Not only did they engage in sports activity, but also devoted themselves to the burdensome daily details of management, thus allowing them to gain legitimacy for the space. They had first occupied the space as baseball players, but had also been undertaking clean-ups, pruning and crime-watch activities in addition to their sports practice. Judgement of whether or not a sports area is a “civic public space” should be based on daily activities essential for administration of the space. “Revitalization of urban life through sport” should not be represented just as an ideal or model, but as the result of efforts to build relations, communications and customs. Urban sociologists should recognize how sports and leisure can legitimize public spaces and help create autonomous communities. Furthermore, sports sociologists should pay much more attention to daily life issues such as creating playgrounds for children in order to legitimatize “sports spaces”.