2019 Spring Starting Pitcher K% Surgers — A Review

Backed by this study supporting the idea that pitcher strikeout rate over spring training does hold some predictive value, I identified and discussed 12 starting pitchers that had posted significantly higher strikeout rates during the spring than my Pod Projection. Let’s see how many, if any, of these pitchers actually outperformed my forecast.

2019 Spring K% Surgers
Player 2019 Pod Projected K% 2019 Spring K% 2019 K% Diff – Pod vs Actual
Robbie Ray 29.7% 45.7% 31.5% 1.8%
Tanner Roark 18.9% 32.0% 21.9% 3.0%
Jordan Zimmermann 18.5% 30.4% 16.3% -2.2%
Shane Bieber 23.4% 34.3% 30.2% 6.8%
Domingo German 24.5% 34.9% 25.8% 1.3%
Luis Cessa 19.7% 30.0% 21.9% 2.2%
Jon Gray 24.4% 33.8% 23.6% -0.8%
Masahiro Tanaka 24.9% 34.3% 19.6% -5.3%
Julio Teheran 21.6% 30.4% 21.5% -0.1%
Justin Verlander 28.3% 36.2% 35.4% 7.1%
Jeremy Hellickson 17.8% 25.3% 16.4% -1.4%
Trevor Richards 22.9% 29.0% 21.9% -1.0%
Unweighted Avg 22.9% 33.0% 23.8% 1.0%

Overall, exactly half the pitchers exceeded my strikeout rate projection and half missed it. A simple unweighted average shows the group outperformed by 1%. So for this sample, spring strikeout rate didn’t mean a whole lot. However, the two biggest gaps between actual and projected strikeout rates were on the upside.

Like any projection system, I’m generally conservative in that I rarely project any metrics to finish at extreme levels. So you certainly won’t find 10 qualified starters projected for a strikeout rate above 30% like we ended up with. On this list, Robbie Ray, Shane Bieber, and Justin Verlander all hit that level and more.

Amazingly, Ray has now posted a 30%+ strikeout rate for three straight seasons. And yet his ERA has climbed each year since bottoming out in 2017. All you need to do is look at both his BABIP and HR/FB rate trend to learn why. But with a big drop in velocity this year, I’m betting 2020 will be the first year his strikeout rate drops back below 30%.

Shane Bieber threw all of his secondary pitches more frequently at the expense of his four-seamer, which is the precise recipe for a strikeout rate jump. Even though his fastball isn’t very good at generating whiffs, both his slider and curve were elite, giving him some downside cushion. He fits in perfectly as an Indians pitcher with a meh fastball, but awesome secondary stuff.

I don’t even know what to say about Justin Verlander. Is the Astros magic really that strong? They did it with Gerrit Cole too, so it could be true. Verlander has now posted his first two strikeout rates above 30% at the tender ages of 35 and 36. That just isn’t supposed to happen.

Tanner Roark’s career best strikeout rate was telegraphed by his spring performance, but it didn’t matter much for his results, as his ERA stood well above 4.00 once again. Remember when we once thought of him as a low BABIP guy because of a .270 mark during his first full year in 2014 and then a .269 mark in another full year in 2016? Well, if those skills were ever real, they are now gone.

What happened to Masahiro Tanaka? He was the list’s biggest loser. His velocity was down marginally and his pitch mix was similar to last year. But all of a sudden his splitter, his best weapon that generated a SwStk% above 20% the two previous seasons, lost half of its whiffiness, with its SwStk% dropping to just 11.2%. I wish I knew why. That pitch is going to be the deciding factor as to whether, and to what degree, Tanaka’s strikeout rate and performance rebounds next season.

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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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I definitely recall reading several times over the course of the season that Tanaka’s splitter was drastically affected by the new ball. He had a much more difficult time gripping his splitter, and so was reliant on his slider instead.


Tanaka also just had surgery on his elbow to remove a bone spur. WOnder how long that was bothering him? Certainly would affect him pitching. But do agree with you the smoother ball affecting his splitter grip likely played a part.


Though he looked great for stretches in the postseason.