ST. PETERSBURG – Mitch Keller never threw a sinker in the minors, despite coming up during a time when seemingly every Pirates pitching prospect was getting a two-seamer pushed their way. “The mentality in the minor leagues for us coming up was fastballs down,” said Keller. Keller had the ability to throw his four-seam fastball … Continue reading How Mitch Keller’s New Sinker Complements His Other Pitches