EVALUATING PITCHER FATIGUE THROUGH SPIN RATE DECLINE: A STATCAST DATA ANALYSIS

This study investigates the correlation between pitcher fatigue and various pitching metrics using Statcast data. Key metrics such as pitch velocities, spin rate, break distance, and release height were analyzed to determine their sensitivity to fatigue. An exponential smoothing algorithm was applied to these metrics to capture the cumulative impact of fatigue over the course of a game. The results revealed that spin rate is the most significant indicator of fatigue, with primary pitch spin rates showing a notable decline. This finding challenges the conventional belief that velocity is the primary fatigue marker. The study suggests that tracking spin rate in real-time can provide teams with critical insights into pitcher fatigue, enabling better decision- making regarding pitcher usage and training. Future implications include the potential for enhanced stamina training and more informed recruiting of starting pitchers based on spin rate stability.