doubleheader
Two games or events played back-to-back in one day.
A doubleheader is when two games are played back-to-back on the same day, usually at the same location. The term comes from baseball, where teams might play two complete games in one afternoon, often because a previous game was rained out and needed to be made up. Fans who buy a ticket to a doubleheader get to watch both games.
In professional baseball, doubleheaders used to be common weekend attractions, giving fans extra entertainment. Today they're less frequent but still happen when weather or scheduling forces two games to be played on the same day.
You might hear the term used beyond baseball. Someone might jokingly say they have a “doubleheader” if they have two soccer games in one day, or even if they're attending both a morning concert and an afternoon play. The word captures that feeling of getting twice the usual action packed into a single day.