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This study aimed to quantify well-done breaking pitches as evaluated by experienced catchers in baseball. Twenty college baseball pitchers threw one pitch for each type of pitch that they typically played in a game. Pitched ball velocity, spin rate, spin component, and displacement were calculated. Nine catchers of the same team evaluated each breaking pitch (curveball, slider, and changeup) of all the pitchers, and the relationships between the catchers’ evaluation and the quantitative variables were then investigated. Thus, with respect to the curveball, significant correlations were observed between the catchers’ evaluation and total spin rate, back spin, and vertical displacement. With respect to the slider, significant correlation was observed between the catchers’ evaluation and ratio of the velocity of the slider relative to the fastball. With respect to the changeup, significant correlation was not observed for any of the variables. The results are expected to act as a good benchmark for pitchers to improve their breaking pitches.