How is a ball ruled if it hits the catcher's mask and rebounds into his glove?

When a ball hits the catcher's mask and then rebounds into his glove, it is ruled as a caught foul ball. This happens because the catcher's mask is considered part of his equipment, and if the ball makes contact with it and is then caught cleanly in the glove, it counts as a legitimate catch. This ruling recognizes that the ball has been controlled by the catcher after hitting the mask, thus allowing the play to be treated as a foul ball rather than a dead ball or any other type of ruling.

In this case, it is important to understand that while some might think the ball is dead or that it doesn't count as a catch, it effectively is viewed as a continuation of the play due to the catcher's successful acquisition of the ball in his glove. The rules are designed to acknowledge the catcher's ability to make a play even when the ball initially makes contact with protective equipment. Runners are not directly affected by this specific ruling, aside from the fact that they are given the chance to advance if the ball was caught foul and the play is in their favor.