What should the fielder with the ball do to begin a run down?

To initiate a rundown, the fielder with the ball should position themselves between the runner and the base they are attempting to reach, ideally cutting off the runner's path. They should then make direct eye contact with the runner and use clear verbal communication to signal their intention to tag them out. As the runner approaches, the fielder should be ready to pivot and throw the ball to a teammate who is strategically positioned to help trap the runner. This coordination increases the chances of successfully tagging out the runner.