When does a slide begin?

[JRutledge]

Originally Posted by Eastshire

Take a foot first slide into a home plate that is completely blocked by a catcher. In a) the runner starts a slide early enough that he is completely on the ground before contacting the catcher and in b) the slide is started late enough that the runner contacts the catcher while still completely in the air, cleats first.

One of these is MC and one is a legal slide and it is entirely due to when the slide started.

You are coming at this from the wrong point of view in my opinion. All contact is not considered illegal or malicious as it relates to calling the game. The OP says basically that the runner was in the process of a slide but ran over the fielder. So at the time of contact there was no slide. Also all slides are not legal. If you come up spikes high, that is not a legal slide. So when it starts is not the issue. If you run into a fielder without actually sliding, then you can easily have MC. Do not make this more complicated than it already is. It is really not that hard.

Peace