What must happen for a batter to be declared out due to a catcher's obstruction?

A batter is declared out due to catcher's obstruction when certain conditions are met. For this to happen, it is essential that all runners on base must advance appropriately, which involves either successfully reaching the next base or being forced to advance because of a play at home plate. The idea is that the obstruction caused by the catcher influences the outcome of the play in a way that the umpire can determine it affects the advancement of runners.

Catcher’s obstruction occurs when the catcher interferes with the batter's ability to swing or hit the ball, and if the play results in runners being held back or unable to advance due to this obstruction, the umpires will rule accordingly. Essentially, for the batter to be called out because of the catcher's obstruction, the umpire must have evidence that the obstruction affected the play and that the runners contributed to the play by advancing appropriately. This ensures that the rules of fair play and advancement are upheld during these situations.

Understanding this ruling reinforces the importance of runners properly advancing during a catcher's obstruction call, as it directly influences whether the batter will be declared out or given another opportunity to bat.