The presence of asymmetry in the relation between attendances and competitive balance in the Australian Football League is tested, over the period 1945-2010. The results from the well-specified structural time-series model validate the uncertainty of outcome hypothesis, and the null of no asymmetry is rejected easily in the structural innovations of the series, although it is not rejected in the levels. The latter finding substantiates the reversibility (without net loss of demand) of league revenue-sharing and labor market policies that influence demand in professional sports leagues.