Prospect Scouting & Stats — Pitcher RPM Break

Yesterday, I identified and discussed the top seven prospect pitchers in RPM FB, which is fastball spin rate. Today, let’s do the same for RPM Break, or the spin rate of the pitcher’s primary breaking ball. While I found that RPM Break is more weakly correlated with the pitcher’s strikeout rate than RPM FB, it’s still positive, and most importantly, is fun to dive into.

Top 7 Prospect RPM Break
Name Org Age Top 100 Org Rk FV RPM Break
Randy Vasquez NYY 21.5 44 35+ 3150
Dustin May LAD 22.6 14 0 60 3050
Bryan Abreu HOU 23.0 5 45 3000
Steven Jennings PIT 21.4 23 40 3000
Keider Montero DET 19.8 28 35+ 3000
Enoli Paredes HOU 24.6 13 40+ 2950
Blaine Knight BAL 23.8 30 35+ 2950

For context, in 2019, the leading average MLB slider spin rate from those who threw at least 50 sliders, was 3,270, followed by 3,246, and then a host of players between 3,000 and 3,100. The leading average MLB curveball spin rate from those who threw at least 50 curves, was 3,431, followed by 3,305.

Our RPM Break leader is none other than Randy Vasquez, a Yankees prospect who we haven’t talked about yet, likely because he earned just a 35+ FV. His high RPM breaker is a curve, which graded out at 55 at present. So far, he has been stuck in the Rookie league and has struggled with his control.

Dodgers prospect Dustin May appeared on some previous lists and also owns the minors’ second highest breaking ball spin rate. That spin rate relates to his slider, which was graded at 60. However, the pitch hasn’t done much for his ability to generate whiffs or strikeouts. Instead, he relies on excellent control and a ground ball tilt to go with his merely average strikeout stuff.

Bryan Abreu has also appeared on lists previously, as amazingly he owns three pitches graded at 60 and higher. Since he throws a slider and curveball, I’m not even positive which breaking ball this RPM Break value relates to. However, in his cup of coffee with the Astros in 2019, he threw his curve 65% of the time, and it generated a spin rate of 2,986, which is super close to the mark on THE BOARD. That spin rate ranked 17th out of 454 pitchers who threw at least 50 curves, and led to an insane 27.4% SwStk% for the pitch. He’s someone to watch.

Despite a solid spin rate, Steven Jennings has posted pedestrian strikeout and SwStk% rates throughout his minor league career. His mediocre breaking ball pitch grades don’t offer us hope for much better in the future either. With a rising fly ball rate as well, he shouldn’t be anywhere near your prospect radar.

Perhaps Keider Montero’s curveball spin led to a strikeout rate breakout at High-A in 2019, but oddly, it came along with just a high single digit SwStk%. Unless he could generate more whiffs, I don’t see how he could repeat a high 20% strikeout rate.

Enoli Paredes is another Astros prospect and aside from his 2017 stop at Single-A, has posted strikeout rates above 31% throughout his minor league career. Judging from his pitch grades, he seemingly has quite the repertoire and it’s backed by elite SwStk% marks. The walk rate has been high though, so as usual, that will be key to his future success. He has oscillated between the rotation and bullpen, so it’s unclear what his future role is going to be. Obviously, root for a starter, unless he looks like a sleeper to save games.

An Orioles pitching prospect? Sure, but Blaine Knight doesn’t appear to actually be a good one. For all that spin, his strikeout rate was more than cut in half upon his move up to High-A in 2019, finishing at a paltry 14.6%. His SwStk% also fell into the high single digits, while he remained a fly ball pitcher. That actually makes him look like a great fit for the Orioles staff! But that also means he doesn’t deserve to be anywhere near your keeper league team.

We hoped you liked reading Prospect Scouting & Stats — Pitcher RPM Break by Mike Podhorzer!

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Mike Podhorzer is the 2015 Fantasy Sports Writers Association Baseball Writer of the Year. He produces player projections using his own forecasting system and is the author of the eBook Projecting X 2.0: How to Forecast Baseball Player Performance, which teaches you how to project players yourself. His projections helped him win the inaugural 2013 Tout Wars mixed draft league. Follow Mike on Twitter @MikePodhorzer and contact him via email.

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