[greymule]

I've never seen any rule, in softball or baseball, that specifies permissible and impermissible areas for a fielder's foot on a base.

The play you described is just another example of the kind of stupid things that happen because kids are not coached properly (or simply forget or ignore what they are told). How many times have you seen a fielder stand in front of a base to catch the ball while the runner slows down and goes in standing up as the ball arrives? Bump! And both coaches file a grievance with you.

I sometimes played F3 in LL. Nobody had to tell me to put my foot on the side of the base. But back in 1960 every kid played sandlot baseball and had already figured that one out.