The purpose of this study is to analyze the physical layout of professional baseball facilities in America from 1850 to 1903 and to identify those instances and conditions of modernization that changed those structures. The information provided demonstrates baseball facilities started out as simple open fields with little or no standardized territories hosting unsophisticated and spontaneous ball games. Next, standardized rules of play prompted baseball facilities to form into small, hastily constructed but temporarily open competition areas that separated participants from spectators. Baseball facilities further evolved into complex temporary enclosed structures to improve spectator experiences and maximize revenues for sport entrepreneurs. However, semi-permanent professional baseball superstructures emerging toward the end of the nineteenth century failed to match the ever-increasing maturity of baseball, its growing stakeholder groups and their concerns, or utilize the improvements offered by available technology.