This advanced metric hints KC Royals' Cole Ragans is about to hit another level

With its fresh way of evaluating pitchers and pitches, Stuff+ has recently been a hot topic around baseball circles — and one Kansas City Royals hurler is getting noticed.

Last season, starter Cole Ragans' fastball tied him at second-best amongst starters with a minimum of 140 innings pitched, earning a 107 Stuff+ score. Only trailing Bryce Miller, Ragans' fastball averaged 95.4 mph with significant "ride," providing a powerful baseline against which the rest of his pitches can be compared.

So what is Stuff+, and what do Ragans' impressive scores mean for the Royals?

What is Stuff+?

While the actual formula for calculating Stuff+ is not publicly available, the pieces of information used to generate the score are known. Several factors go into Stuff+, including pitch velocity, spin rate, and axis, as well as the movement and release point of the pitch. By analyzing this data, league averages are assigned to both pitchers and the specific types of pitches they throw, establishing a baseline — 100 is league average — to use when comparing pitchers to each other.

While it's arguably an oversimplification, Stuff+ can be looked at as a measurement of how difficult a pitch is to hit compared to other pitches, based on its physical characteristics. A pitch with more unexpected movement — for example, a higher velocity pitch with high vertical break, or a sharper-breaking sinker from a lower release point — will rank with greater "stuff."

Cole Ragans' 2024 Stuff+ score bodes well for continued success with KC Royals

Stuff+ measures each pitch independently, but since the fastball lays the groundwork for the rest of a pitcher's arsenal, comparing secondary pitches to the fastball is a strong indicator of on-field success. As mentioned above, Ragans's fastball earned an impressive 107 Stuff+ score in 2024, and that was in no small part due to seam-shifted wake.

When a ball is in flight, the seams creating disturbance in the air flow around the ball on one side more than the other. This can create loft, which encourages deep vertical breaking movement in curveballs and sharp horizontal movement on fastballs and sliders. Ragans' fastball not only plays up in the zone but — thanks to his understanding of seam-shifted wake — brings a serious 12.6 inches of movement inside to right-handed hitters.

So, what about his other pitches?

After his fastball, Ragans' most used pitch is his changeup, which earned a Stuff+ score of 110 in 2024 to rank sixth amongst hurlers with at least 140 innings pitched, only behind fellow-Royal Michael Wacha, Tarik Skubal, Nick Martinez, Cristopher Sánchez, and Carlos Rodón. With 12.3 inches of induced vertical break and 16 inches of arm-side movement, it is a devastating pairing with his fastball, generating a 47.8% whiff rate.

Still, Ragans' most highly rated pitch is his slider. With an incredible 128 Stuff+ score last season, his slider ranked fourth amongst starters with at least 140 innings, only behind Garrett Crochet, Corbin Burnes, and Aaron Civale. Ragans only began throwing a slider in 2022, but from 2023 to 2024, it went from his fifth most-utilized pitch to his third most-utilized. With a strikeout rate of 44.4%, his slider nosedives toward the shins of right-handed batters, making it one of his very best put-away pitches to righties.

While, Stuff+ only looks at how a pitch acts and doesn't consider what happens after it reaches the plate, it's still a fantastic indicator of a pitcher's ability. After an incredible 2024 campaign with the Royals, Ragans is locked in to lead the team's rotation this season, and if he's able to replicate even some of the Stuff+ scores he put up last year, Kansas City should be very excited.