Complex interactions between high-skilled migration and aggregate performance govern the dynamics of growth and inequality across nations. Due to lack of data, these interdependencies have not been extensively studied in the economics literature. This paper takes advantage of the availability of rich panel data on the mobility of talented football players, and the performances of national leagues and teams to quantify the effect of a "globalization" shock, the 1995 Bosman rule, on global efficiency and cross-country inequality in football. I built a micro-founded model endogenizing migration decisions, inequality and training; I estimated its structural parameters; and I used numerical simulations to compare actual data with a counterfactual no-Bosman trajectory. My analysis reveals that the Bosman shock (i) increased global efficiency in football, (ii) increased inequality across leagues, and (iii) decreased inequality across national teams. I quantify the effect of the Bosman rule on the football hierarchy of UEFA and FIFA. Countries from Africa, South (except Argentina and Brazil) and Central America have produced more talents and benefitted from brain-gain type effects. My results also show that this brain-gain mechanism is the major source of efficiency gains. However, it plays only a minor role in explaining the rising inequality.