Infield Fly Double Play Ruling

Question
When an IF rule fly is caught and runners have left base early, must they be tagged out or can the fielder throw to the base like a normal and beat the runner with the throw to the baseman?  I would like the rule cited as I cannot find it.

Thank you

Answer
Hi gregg

an infield fly is like any other fly ball only the batter is out while the ball is still in the air.

if the ball is caught the runners must stay on the base until the ball is touched or be liable for leaving early, just like any caught fly ball.  Either a tag off base or a fielder in control of the ball in contact with the base before the runner returns.  Both of these are live ball appeals of a base left too early and are timing plays not force outs.

ASA 87f

Mark