I recently read a biography on Koufax: Lefty’s Legacy. In it Koufax describes how he places his posting foot or his left foot not beside the rubber but on top of it?
If you watch in this film off Chris O’Leary’s site you can see it: watch his left foot and its placement on the rubber.
Koufax claims that this is a big part of his velocity since it forces his hips to go forward when he lifts his leg.
Can anybody tell me if they do this? Or if anybody thinks this could add more velocity to a pitcher? I have trouble not getting enough momentum so could this change from side of the rubber to top of rubber help me?