An Exploration of Stuff+ at the MLB Level, Part I

A quick look at Stuff+ data from Fangraphs + the daily report from around the minors

Pitch modeling has become extremely popular in the last few years — and for a good reason. While it’s not the end all, be all, it helps cut through the noise and gets closer to evaluating the pitches in a pitcher’s arsenal that most closely accounts for their ability to control the flight of the baseball. There are plenty of public models out there, but the versions available on Fangraphs include metrics from Eno Sarris of the Athletic and from PitchingBot.

Let’s start at the team-level in 2023. Here is a look at Stuff+ for each MLB team, looking at starters and relievers on each axis. The Rockies are removed because Stuff+ is not adjusted for altitude and they are really, really low for both. You want to be in the upper right quadrant, indicating you possess both starters and relievers with above-average Stuff+ ratings. It’s not surprising that most of the teams likely headed to the postseason can be found here.

It’s a bit surprising how good the Yankees stuff has been given the mediocre results overall. Obviously, injuries have been the issue in New York — Carlos Rodón doesn’t even make this list because he’s only thrown 27 innings this season.

Outside of the Rockies, how about the club whose starters have the worst Stuff+ — that would be the Kansas City Royals, who don’t have a single starter with above-average stuff on their staff. Yikes. Brady Singer has the highest rated Stuff+, but is still well below-average. The Royals don’t have a single starter who has a strikeout percentage higher than 20%.

Who has Underperformed Relative to their Stuff+?