Hosting professional sports teams is often seen as a financial benefit for cities. In the following analysis, we provide evidence that sports teams also carry costs. The analysis, the first examining a Major League Baseball team, finds significant increases in a variety of crimes during home game days of the St. Louis Cardinals. Adjusting for attendance and game length, this study finds that larcenies, motor vehicle thefts, minor assaults, disorderly conduct, and destruction of property increase in volume during game days. Increases concentrate especially around the immediate stadium area, but some are also observable in citywide levels of crime. Additionally, this study examines differences between the time of day a game is played and games played against its historic rival, the Chicago Cubs.