Pitcher Spotlight: J.A. Happ, Strikeout King

The first few weeks of the season often produce entertaining statistical extremes. Wild ERAs, over-the-top “on pace” numbers, and inflated ratios that give us a sensible chuckle as we collectively understand the lack of truth they hold.

Often among these novelties are the early league-wide leaderboards. I elected to pull up the 2018 strikeout leaders and here is what you’ll see:

2018 MLB Strikeout % Leaders
Rank Player Strikeout Rate
1 Gerrit Cole 39.8%
2 Max Scherzer 38.4%
3 Noah Syndergaard 37.9%
4 Lance McCullers Jr. 37.4%
5 Patrick Corbin 37.0%
6 Chris Sale 36.5%
7 Justin Verlander 33.7%
8 Charlie Morton 33.3%
9 Robbie Ray 33.0%
10 J.A. Happ 32.0%

It’s filled with names you expected. The Houston trio of Cole, Verlander, and Charlie Morton are killing it out of the gate. Scherzer, Ray, Syndergaard, Sale, of course they would be here. Corbin? He’s been on fire!

At the very end, something doesn’t feel right. Like the sole freshman on the varsity team inside the very first meeting of the year, quietly sitting at the bottom of the list and questioning why he’s even there, J.A. Happ raises his hand to meekly say “…Hi.”

After holding just a 22.7% strikeout rate in 2017, Happ has been a different animal in 2018 with a remarkable 32.0% strikeout clip. He’s been especially productive in his last three starts, recording 26 strikeouts in just 17.1 innings. It’s wild and ridiculous, but most importantly, it’s fun. It gives us an exciting question to answer: Just how is he doing this?

Happ isn’t supposed to be a strikeout pitcher. He holds a 20.4% career mark. His previous high was 23.0% in 2012 and has never recorded a whiff rate in double digits. This year, that number is 14.3%, good enough for 11th best in the majors. This isn’t just a product of luck, something has to be different.

Here’s what I’m seeing. Happ is a fastball-heavy pitcher with the occasional slider and changeup plus a surprise curveball. While his sinker hasn’t seen much difference since last season – used roughly 25-30% of the time – his other options have returned wildly different results:

J.A. Happ 2017 + 2018 Arsenal
Pitch Type Year Contact % Whiff %
Four-Seamer 2017 75.7% 11.2%
Four-Seamer 2018 65.3% 17.8%
Slider 2017 80.2% 8.4%
Slider 2018 70.8% 13.7%
Changeup 2017 75.2% 11.0%
Changeup 2018 60.0% 17.7%

His slider and changeup have returned plenty better results, but keep in mind, they make up less than 25% of Happ’s repertoire and a 13.7% whiff rate on a slider is below-average, while a 17.5% mark on a pitch thrown just 8.7% of the time can’t be the sole catalyst for this kind of bump in performance.

But then there’s this four-seamer that stares you in the face. It’s rare to see a four-seamer hold a 17.8% whiff rate. It’s also rare to see a starter feature its best whiff rate with his four-seam fastball. That 65.3% contact rate on his heater? Yep, super rare for a starter.

You get it. J.A. Happ is doing a very rare thing.

You may be able to guess how Happ is doing this. If you haven’t, this should help:

You’re looking at a pair of heatmaps featuring four-seamer locations against right-handed batters. The left is from 2017, the right grabs from the small 148 pitch sample of 2018.

Happ is elevating four-seamers nearly exclusively against right-handers and they just don’t know what to do about it. Let me show you some examples as I purposefully pulled pitches across each of his four starts:

Notice that not all of these pitches are strikeouts. Throwing up in the zone isn’t a new approach from Happ as he earned plenty of punchouts using the pitch last season. It’s the fact that he’s staying so exclusively elevated always that has turned his pitch into one of the better heaters in the game thus far. Happ had plenty of success in two-strike situations, but instead of saving the weapon to end at-bats, he’s using it to earn strikes early and as a putaway offering.

You could even say that Happ is McCullersing with his four-seamer, as weird as that sounds. The philosophy is to resist saving your best pitch in favor of increasing its usage and whipping it out in all situations. And it’s working.

This article is all about Happ’s new four-seamer approach and I saved one last table for the end. It’s a special one:

J.A. Happ’s Four-Seamer
Usage % Contact % Whiff % O-Swing BAA ISO Line Drive % pVal
2017 42.3% 75.7% 11.2% 22.7% .233 .219 28.0% 2.1
2018 47.2% 65.3% 17.8% 29.3% .103 .103 11.1% 5.0

In just four starts, J.A. Happ has already more than the doubled the value out of his four-seamer from the entirety of his 2017 season. It has improved in every metric from improved batted ball results, increased chases from batters, and more swings-and-misses. While his 4.50 ERA hasn’t been a proper representation of this change in approach (thanks, 27.8% HR/FB rate!), a 32.0% strikeout rate suggests that when the home run regression hits, we may have some incredible outings ahead.

We’re dealing with a sample of just 148 pitches across 22 frames and we shouldn’t be expecting this level of success through the entire season. Still, those that see an early run from Happ and write it off as an April anomaly should question their decision. Happ returned a 22.7% strikeout rate in 2017 and a full season at 25% is well within reach given the dominance of his four-seamer – a pitch he throws nearly 50% of the time. There may be a buy-low opportunity here and I would love to take advantage of it.

We hoped you liked reading Pitcher Spotlight: J.A. Happ, Strikeout King by Nick Pollack!

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Nick Pollack is the founder of PitcherList.com and has written for Washington Post, Fantasy Pros, and CBS Sports. He can be found making an excessive amount of GIFs on twitter at @PitcherList.

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Hayves
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Hayves

did you look at his Pittsburgh data? I could have sworn this was what he did there to get a ton of Ks