Question came up during NCAA fall-ball game. Runner stealing home. Pitcher speeds up delivery, but does he have to keep same, identical motion? Rule reads from windup and set once his natural movement begins....."commits the pitcher to pitch without interruption or alteration." Same thing with set position, where we do see the "slide step" more in use.

Tks,

CVA

Keep reading the rule book until you get to 9-3(d) AR. That will answer your question.

Tks Bob. Nothing worse than a bunch of old umps (here) nitpicking stuff. Yep, familiar with 9-3D. Says "a normal pitching sequence...etc" but not HIS normal sequence. I am saying he does not have to keep his regular windup motion as long as it does not violate pitching rules. I think you are saying the same thing, but not certain.
Tks,
CVA

You got it. Show the rule to the old umps. It's the only way we learn.

Tks. Will do. Have a great day.