Roy Halladay's Pitches

Roy Halladay has an array of pitches that he uses, and just got even better this season by modifying his changeup to create a different movement while using it more often. Looking at Halladay's pitch type table at Fangraphs, he is using his new changeup 12% of the time this season compared to less than 5% in previous seasons.

I wanted to take a look at Halladay's different pitches to see which ones he gets the highest percentage of swinging strikes off of. The best step to take in order to compare pitch types would be to generate run value heat maps, but seeing as that I still am experimenting with contour heat maps and local regression models, let's keep it simple first (just in case there are mistakes again). Also, I will be sampling at least 1000 pitches for most of my maps from now on. So instead of looking at his changeups, let's take a look at the swinging strike probability models on Halladay's other great pitches, the four-seam fastball, cutter, and curveball:







Halladay, a right-handed pitcher, gets swinging strikes on high four-seam fastballs against right-handed hitters and high and inside fastballs against left-handed hitters. His cutters go outside on RHH and inside on LHH, getting RHH to whiff on cutters in the zone and LHH to whiff low and inside. Halladay's curveballs are the real meat here in terms of getting batters to whiff, as around 30-40% of curveballs thrown down and away from RHH and down and inside to LHH get batters to whiff.

What can I say? Halladay is one of the best pitchers in our generation, and I haven't even showed the results of his changeup yet. According to Fangraphs' pitch type values for Halladay, his cutter is his most valuable pitch, followed by his curveball, four-seamer, and changeup. But it's his new changeup that's been the most improved since last season, after he made adjustments to the grip on his changeup this offseason.