Pitcher stumbles on pick-off attempt

[jstone999]

Didn't see this, but it's being discussed on a local umpire forum in Germany. Last weekend, White Sox against the Dodgers. Pitcher attempts a pick-off to first from set position (without disengaging) but stumbles during the attempt and overthrows first. Blue gives TWO bases.

Did anyone see this? Why two bases? Does stumbling during the throw constitute disengagment, or did the umpire blow the call, or what else could explain awarding two bases on a pick-off overthrow?

jeffstone
goettingen