Book excerpt: For decades, sports economics has been set within the framework of equilibrium economics, in particular when modelling team sport leagues. Based on a conviction that this does not reflect real life, this book addresses a gap in the literature and opens up a new research area by applying concepts drawn from disequilibrium economics. It is divided into two parts, the first of which focuses on economic disequilibrium in sports markets and competitive imbalance in sporting contests. The second part concentrates on soft budget constraints and their consequences for club governance and management.