Bat and baseballs; Helmets
Start with runners on first and second and one player in the batters box. Have all other runners in a line behind home.
Have a coach in the third base box and another coach out in front of home with a bat and baseballs.
Coach will hit a ball to any part of the field. All ground balls will be considered to be through for a base hit. All fly balls will be considered singles also.
All baserunners will behave as if there is a defense.
Hitter will run hard through first base on a ground ball
He will round the base on a ball hit in the air to the outfield.
Either way he stays at first base.
Runner at first will run hard strait into second on a ground ball to the infield.
Runner will pick up the third base coach on any ball hit to the outfield. The third base coach will then instruct the runner to either stay at second or proceed to third.
runner at second will go straight into third on a ground ball.
On a fly ball he will round third and pick up the third base coach to determine whether he will score or not.
Runner at third will tag on a fly ball and run when the ball hits the ground. If there is no runner on second, the third base coach can give the runner instructions on what to do on a ground ball. "Score on all balls except back to the pitcher".
Keep it moving. Players need to quickly analyze the situation and be ready to move.