A term in baseball that refers to a play that occurs when a baserunner is caught between more than one defensive player when attempting to advance or return to a base.
A rundown most often occurs when a baserunner is either attempting to steal a base, return to a base on an aborted steal, or is attempting to advance to the next base while the ball is in play. A rundown is only necessary when there is no force play available to the defensive team-the stranded baserunner must reach a base safely without being tagged out. Most rundowns result in the baserunner being tagged out as fielders can advance while throwing the ball between them, diminishing the space in which the runner is able to move. Normal rules for staying within the base paths apply during a rundown, so a baserunner cannot deviate from the base path too widely or he is automatically called out by the umpire. Likewise, if the runner interferes with a fielder's attempt to throw or tag him out during a rundown, he will often be called out.
Runners will sometimes intentionally attempt to be caught in a rundown if they are the trailing runner, in order to distract defenders from making an out ahead of them.
A rundown is also colloquially referred to as a "hotbox" or "pickle."