Your Reaction ???

[Bandit]

College game. 0 outs. Bases loaded. Your the umpire in "C" position. Infield playing tight but not reaaly in super close. Batter takes a full swing and hit the ball off of the end of the bat and towards the third baseperson. Runners are off as soon as they realize it's on the ground. Runner from third is sliding cleanly into home. Contacts catcher. Everything clean. Third base person has under hand tossed the ball towards home plate for the force but the ball hits the runner in the back. Ball rolls to front of plate and runner who has defintley scored has a "brain fart" and starts to pick-up the ball. Within a split second drops the ball right where she picked it up. Home plate umpire never comes to you. What would you do ?