Participants of dynamic contests sometimes play with the rules of the game by withholding effort in the beginning. Such behavior is referred to as sandbagging. I consider a two-period contest between heterogeneous players and analyze potential sandbagging of high-ability participants in period one. This sandbagging can be beneficial to avoid second-period matches against other high-ability opponents. I characterize the conditions under which sandbagging leads to a coordination problem, similar to that of the battle of the sexes. Moreover, if players' abilities have a stronger impact on the outcome of the first-period contest than effort choices, mutual sandbagging by all high-ability players can arise.