Some coaches teach their players to throw and run to the inside of the base path. Others prefer that their defense remain to the right side, since most infielders are right-handed. Either way, criss-crossing the base path is asking for trouble. If the runner tries to obscure your fielders' throws or vision, they should move further to the chosen side. The ball handler sprints toward the runner forcing him to abandon his shuffle steps, square his shoulders, and retreat at full speed.
Speed is crucial.
It exposes the runner's inherent vulnerability in rundowns. While sprinting, the infielder holds the ball steady beside his ear ready to tag or release at any instant. The trail base fielder presents his glove as a visible target and is poised to move toward an arrant throw, just in case. As the runner approaches within 6-8 feet of the receiving fielder, the ball handler gains control of his body and throws. The baserunner will consume precious seconds coming to a complete stop and changing direction.