Detroit Tigers: Spencer Turnbull-Turn and Spin

The Detroit Tigers have a spin doctor on their hands. Spencer Turnbull. No, not like the 90s band.

It’s wonderful to have Detroit Tigers baseball back. For some of us, it means we get to discuss live games on Twitter again, which naturally lends itself to moments of exuberance that veer dangerously close to hot takery. Case in point one from my podcast partner and fellow co-expert:

Instead of just chalking this up as the ravings of a madman err I mean wishful thinking of my overzealous co-expert, we thought maybe it would be fun to try to put it to the test as we team up to dig up some interesting data.

We have a general idea of the stuff of Detroit’s top three pitching prospects: Tarik Skubal has an electric mid-90s fastball, Matt Manning has a powerful fastball/curveball combination, and Casey Mize has a broad arsenal highlighted by a terrific cutter and a diabolical splitter.

Unfortunately, without access to minor-league TrackMan data or big-league performance (pretty diabolical of Chris to make claims that can’t be measured), we can’t really compare Turnbull’s pure stuff to the top prospects.

The next best arms (among starters, at least) in the organization are probably Michael Fulmer, Matthew Boyd, and Daniel Norris. We can and will compare their stuff to Turnbull’s one day, but as we dug into Turnbull’s pitch data we noticed something that quickly altered the focus of this piece.

The spin rate on all of Turnbull’s pitches was up yesterday. Way up.

Spin-cer Turnbull?

Now, raw spin rate numbers don’t necessarily tell us much. Not all spin is useful, and pitchers need a lot more than just big spin rates to succeed. That said, the 4-seam spin rate leaderboards tend to have a lot of dominant arms at the top.

In 2019 Turnbull’s four-seam fastball had an average spin rate of 2,396 RPM. That was above average, but not particularly special. Among 53 pitchers who threw at least 1,000 four-seamers last year, Turnbull’s spin rate ranked 17th, just ahead of Norris (19th) and Boyd (20th).

But in Sunday’s start against the Reds, Turnbull’s average four-seam spin rate vaulted to 2,563 RPM. That’s good for the fifth-best in baseball this season (minimum 25 pitches), and last year it would’ve ranked as the third-highest spin rate, right between Gerrit Cole (2,530) and Justin Verlander (2,577).

Similarly, Turnbull’s slider rose from an average spin rate of 2,438 last year to 2,549 on Sunday. That’s enough to move his slider spin from roughly the 54th percentile to the 72nd percentile. His sinker (+193) and curve (+80) also saw big rises in spin, though the sample sizes are awfully small.

So we see a big rise in spin rate, but did it actually make a difference? Anecdotal evidence suggests it did.

Turnbull threw 87 pitches yesterday, and according to Statcast, Reds batters swung at 34 of them and missed 17 times (15 whiffs and 2 foul tips). Those 17 swings-and-misses are the highest raw total of Turnbull’s career, and the 50% swing-and-miss rate is the best of his career by more than 12%. The nine swings-and-misses on his slider were a new career-high.

Cincinnati hitters put 10 balls in play on Sunday, at an average exit velocity of 80 mph. That, too, was a career-best for Turnbull, by more than two miles-per-hour.

It was just one start, and it’s still very early in the year, so perhaps hitters are just behind. Maybe the sun was unusually harsh to hitters. But Spencer Turnbull may have just had the best start of his young career yesterday, and it looks like it could be due to newfound spin.

We’ll keep an eye on this for the rest of the season to see if this was just a blip, or something real.

The Other Kind of Spin

Our educated readers are no doubt aware Major League Baseball has updated Statcast to use Hawk-Eye pitch-tracking technology rather than TrackMan. It is possible Turnbull’s newfound spin is a result of pitch classification errors. For example, this pitch to Joey Votto registered as a 4-seam fastball with an absurdly high spin rate of 3007, which was 335 RPM higher than his next highest-spin four-seamer.

However, other high-spin pitchers like Cole and Max Scherzer have seen their four-seam fastball rates stay relatively static this year compared to 2019. Scherzer’s spin rate was up 23 RPM while Cole’s was down 27.

But it does seem possible, if not probable, that there was something strange going on specifically with the pitch measuring equipment in Cincinnati on Sunday. Gregory Soto, Michael Lorenzen, and Amir Garrett all posted average four-seam spin rates close to 100 RPM higher than in 2019, though Joe Jimenez (-109), Pedro Strop (-62), and Jose Cisnero (-95) all saw large drops.

But the biggest red flag comes from Cincinnati’s starter Trevor Bauer, whose average four-seam spin rate on Sunday was 2,817 RPM — more than 400 RPM higher than last season.

Bauer is no stranger to spin-rate controversy, so perhaps something else was at work here. Maybe he and Kyle Boddy devised some dastardly new way to increase spin. Or maybe the numbers were just wonky across the board. Only time will tell.