"a runner is not allowed to remain on her feet and crash into a fielder in possession of the ball. When this situation occurs, interference should be ruled. The runner involved in the collision is called out, any other runners must return to the last base touched at the time of the collision (unless forced to advance), and the batter-runner is awarded first base.

However, umpires should watch the play develop and finish in case the contact is severe, then be prepared to rule accordingly. The NFHS code includes a definition of malicious contact — “an act that involves excessive force with an opponent.” The penalty is ejection for the offender.

A sign that excessive force might be involved is when the fielder holding the ball ends up on the ground. For example, a runner who remains on her feet and forcefully pushes the fielder with both hands should be ejected in most cases."