The slider-curve hybrid has been around for more than 50 years. Corey Kluber won two Cy Youngs with it. So why is it just catching on now?
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ST. PETERSBURG, Fla. — Corey Kluber has long said that his breaking ball resists classification. It’s not a curve. It’s not a slider. It’s just his breaking ball—the pitch that helped him win the Cy Young in 2014 and ’17, and that still bedevils hitters today, with far more horizontal break than a traditional slider yet less drop than a traditional curve.