left foot

[alex7]

Now that I'm told he's facing third, I'm thinking...

If he's not considered engaged with his left foot on the rubber, then I guess he's just an infielder and can do whatever.

If he is deemed to have engaged the rubber with his left foot...

1.) You give him the FED balk for not engaging the rubber with his throwing side's foot.

Cbfoulds, if his left foot is ON the rubber, I'm not sure that's the same as straddling the rubber. This doesn't seem to be a case of a guy just getting comfortable into his stretch position, where he can do a a little funky footwork. The OP says the guy "mounted" the rubber (insert sex joke here).