Pitch Framing
A catcher receiving a borderline pitch so it gets called a strike.
How it actually works. Tracking data made it measurable around 2013 and the answer surprised everyone: the best framers were worth more than a win a season over the worst, purely in called strikes.
Why it is done, and when it is wrong. It reordered how catchers were valued, and several careers were saved by it. Automated ball and strike systems, wherever they arrive, will delete the skill entirely, which makes it the rare baseball ability with an expiry date.
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