The balk is one of the most confusing rules in baseball, so let's go over a simplified version of this complicated rule real quick:
A balk occurs when a pitcher makes an illegal motion on the mound that the umpire deems to be deceitful to the runner(s). As a result, any men on base are awarded the next base, and the pitch (if it was thrown in the first place) is waved off for a dead ball.
Essentially, for this next situation, if you're making a motion toward the plate to pitch the ball, you can't just stop that motion.
Okay, here's Mother Nature causing a balk in the minor leagues down in Jacksonville:

Literally everyone in the stadium ...

... And the ump calls a balk!
Anybody else feel like the ump could've simply given the pitcher the pitch back on that one instead of calling in the runner from third? I mean, lightning striking during a pitching motion, causing the batter to step out of the box isn't really covered in the rulebook.
Either way, Norfolk ended up winning the game, so at least they can't be too upset about the call.
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