Baseball rule check... keep me honest.

[RunN1st]

A good friend is writing a book and has sent me a message asking I fact check one of the scenes. I'm hoping you guys can chime in. I've highlighted in blue the rule in question. Is it a strike if the batter swings before the ball is in flight?

Thanks guys!

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I focused on the pitcher sixty feet away. The guy had an eighty-five mph fastball and a curveball that defied the laws of physics. Which one is he going to throw? I bent my knees, raised my bat and waited.

The pitcher sets, eyes the runner, and throws a fastball low and outside. The blur of white zips across the plate.

Keeping my head steady and my eye on the speeding ball, I fired my rear hip forward and swung hard.

Whoosh! The bat cut through nothing but air.

A full second later, the pitcher released the ball, and it slammed into the catcher’s mitt with a decisive smack.

“Strike three!” the umpire bellowed.

The crowd started booing loudly.

“What the hell?” bellowed Coach Martinez, leaping to his feet and storming out of the dugout. He stared at me with incredulity. “Are you some kind of moron? You swung at the ball before he even threw it!”

“No—it was right in front of me! I saw it!” I stepped out ofthe batter’s box and let my bat drop to the ground. A wave of dizziness coursed through me.

The pitcher from Mesa Heights trotted off the field. “Great hand-eye coordination, Reynolds.”

[ManiacMatt1782]

I would say once the pitcher comes set, any swing that breaks the plate would be a strike, not sure if I am correct, taking a guess without looking it up.

[RunN1st]

Thanks, dude. I also wasn't 100% sure.

[dingleberryfinn]

I don't know why it would need to be in flight.
Hell, I've seen batters swing at the ball after it was already in the catcher's mitt, though that was little league lol

[Beelzebot44]

Until the pitcher releases the ball it would not be a strike. Lots of hitters (myself icluded) have a pre-pitch routine that includes waving the bat over the plate up to and sometimes during the pitcher's delivery.

Basically it's at the discretion of the umpire whether or not a batter has attempted a swing, and I have never seen one call a swing before the pitcher has thrown the ball.