Despite burgeoning literature on the agency of sports coaches and the nature of coaching fields, scant attention has been paid to the process through which coaches' identities are socially constructed. Informed by Goffman's concept, "total institution," and Scott's "reinventive institution," this article explores how coaches' athletic experiences within totalising sports environments influence the formation of their identity as coaches. Drawing on South Korea's elite sports context where almost all high-performance coaches are former athletes who share experiences of being trained under an authoritative sport regime, a qualitative analysis was conducted on data from documents and in-depth interviews with 26 participants. Findings reveal that: (1) individual selves in the coercive sports setting were eroded and rewritten by the totalising nature of the social architecture; (2) nevertheless, the individuals displayed a certain degree of agency in their desire to reinvent themselves in the sports setting; and (3) the nexus of institutional power of the sport setting and voluntary participation of the individual athletes engendered a one-dimensional identity that was optimised only for the elite sports setting. These findings suggest that the identities shaped within South Korea's elite sports environment steered athletes to become coaches upon retirement from sports, reluctantly returning to, or remaining in, their comfort zone -- the totalising environment of elite sports.