Alright, I'll give it a shot. If a runner is going, it's too late to tell the pitcher, who's leg is already raised, to spin and throw without balking. It would require some hesitation on the pitcher's part, which would result in a balk. The move must be in a continuous motion, with no hesitation or stopping of momentum to be legal. In order to execute the spin move, it needs to be a planned out move by the pitcher, not something he thinks about at the last second.

The move is usually just used to drive the runner back to 2nd base so he will shorten his lead on the next pitch, knowing that the pitcher may try to pick him off, and therefore not getting as good a jump on a base hit. That little edge can mean the difference between a runner scoring or being thrown out at the plate.

(Taking off umpiring hat)

Because most pitchers with a runner on first will not take as long in their leg lift and drive to the plate... so there is really no time for somebody to yell at him, him realize, turn to second without ever moving towards the plate or hanging a leg.

If a pitcher can do this, he's probably wayyy to slow to the plate to begin with.

(Putting back on umpiring hat)

[QUOTE=SanDiegoSteve]Alright, I'll give it a shot. If a runner is going, it's too late to tell the pitcher, who's leg is already raised, to spin and throw without balking. It would require some hesitation on the pitcher's part, which would result in a balk. The move must be in a continuous motion, with no hesitation or stopping of momentum to be legal. In order to execute the spin move, it needs to be a planned out move by the pitcher, not something he thinks about at the last second. [QUOTE]

The pitcher isn't likely to hesitate if he knows 100% that the runner is going. Take this situation; 3-2 count, 2 outs, runner on first. Everybody knows the runner is going, so the pitcher should have no problem making a continuous transition from balance point to turning and throwing to 2nd.

The runner shouldn't go until F1 commits to the plate -- that is, starts forward from the balance point. Now if F1 throws to second, it's a balk.

I've seen it but not as umpire. It was one of my son's Babe Ruth games and his team's pitcher did it.

Offensive coach started screaming balk. His runner was able to get back to first safely.

Umpire made the right call.

Rita

I think it might be as simple as what you see as the balance point and what others see as the balance point are different.

At the pro clinics I've attended we were taught that the RH pitcher is allowed to step to first and throw as long as his leg rise, did not simulate the leg rise of his delivery and that the intial direction of that step was smoothly and continuously toward first.

In practice, they concentrated more on the distance of the foot coming up rather than the knee, and they didn't allow it to come up very far.

I have seen this move in the pros, but it occurs far less than a jump turn, jab step or disengaging. The fear of a balk may well play a part in that.