Drew Hutchison's New and Improved Slider

Within the next month or so, Max Scherzer will sign a contract that could set a record for the biggest contract ever given to a pitcher. He's in line for a guarantee of at least $150-million, and maybe upwards of $200-million. And with good reason, as he's been a top-3 starter in MLB the last 3 seasons, no history of injury problems, and will start next year at 30. Come to think of it, Scherzer would look really good atop the Blue Jays rotation in 2015.

Of course, that's a complete pipedream, as Scherzer will get an annual salary beyond what the Jays can fit into their budget, will sign for more years than the Jays limit of 5 years for free agents, and is a Boras client. Tant pis. But what if I was to say that the Jays already had a starter who, in the second half of 2014, was almost as good as Scherzer in a numerous key ways (and not because Scherzer was bad, quite the contrary):

By the headline numbers, Drew Hutchison isn't even a very poor man's Scherzer, his ERA two full runs above Scherzer. They were on polar opposites of league average, Scherzer about 25% better and Hutchison 25% worse. Even looking at components, Hutchison's FIP was well over a run higher. But normalizing for home runs, they were a lot closer, with xFIPs just half a run apart. SIERA, incorporating non-linearity and batted balls, gives Scherzer a small advantage but sees them as having pitched almost equally pitched as well.

Indeed, looking at what pitchers have the most control over (K and BB), Hutchison and Scherzer were very similar in the second half. They walked batters at essentially the same rate, and Scherzer struck out just 1% more batters. The big difference was home runs, where Hutchison gave up a significantly higher amount of fly balls, and had them leave the ballpark at nearly twice the rate. This was the major difference between them, in addition to sequencing differences.

Interestingly, while Hutchison gave up a lot more fly balls - second highest rate among 101 qualified SPs - he also induced slightly more ground balls, meaning those extra fly balls were coming at the expense of line drives. While that will lead to more home runs which is definitely not good, it's actually not a bad tradeoff at all since MLB hitters are overall far more productive on line drives (2014 wRC+ of 356 for non-pitchers on liners v. 115 for fly balls). This is a large part of the reason that SIERA found much less of a difference than xFIP.

So why the focus on the second half only? To highlight the fact that Hutchison took a pretty big step forward in the last three months of the year compared to the first three months:

These numbers don't match up exactly with the numbers above, since filtering by "second half" uses the All-Star break to divide; whereas doing it by month divides Hutchison's season into perfect halves, 16 starts and 92.1 innings each. Once again, the headline numbers skew the improvement, but digging deeper it's pretty clear.

From April to June, Hutchison was the definition of a league average pitcher: average ERA, average FIP, average xFIP, average K%, average BB%, average HR/FB rate, average BABIP, average LOB%. The only deviation was Hutchison's fly ball orientation.

In the second half, Hutchison's ERA ballooned while his FIP declined and SIERA plunged. This is because he improved his K% materially by 6% from 20.3% to 26.5% while holding his walk rate mostly constant. He allowed more home run because he allowed 6% more fly balls, which FIP/xFIP don't like, but again at the expense of line drives, which SIERA really likes. I would expect the line drive rate to regress back toward league average, but coming mostly from fly balls since his ground ball rate has been pretty stable.

In September, he took this to more of an extreme, striking out a crazy 35% of batters but giving up a pile of home runs. The home run rate can easily dismissed as noise in such a small sample, but the increased K rate can have some inferential value even in such a small sample. That said, it was September with expanded rosters, one of those starts with against the Cubs who were playing a lot of call ups, two against Baltimore who had the division wrapped up, etc. So we don't want to read too much into it, but it's worth noting his last two starts of August against TB and NYY were similarly good.

If Hutchison can maintain a strikeout rate in the mid-to-high 20s while doing everything else similarly, it increases his value substantially. Not only does it make him a breakout candidate, but he's probably more of a top-50 pitcher rather than top-100 or so (back/midrotation) starter in MLB. I'm certainly not the first to notice this uptick, for example Rotographs' Mike Podherzer and Gammons Daily's Alec Hopp. Both pointed to some changes, but neither in my view pointed to a fundamental improvement that would explain such a big increase in strikeout rate. And that's really the key is Hutchison is to actually break out.

Watching Hutchison in 2014, one thing I thought I noticed was that in the second half he was doing a much better job of consistently "finishing" his slider and the getting late break that leads to swings and misses. Such anecdotal observations are notoriously unreliable - it's easy to remember a couple of good pitches and forgot a bunch of bad ones especially if they weren't punished - so it's something I filed away to look at the winter comprehensively. And when I did get around to it over the holidays, I was actually really surprised with that I found.

Starting with the vertical break on Hutchison's pitches by month:

Over the first four months, Hutchison got no vertical movement on his slider (relative to the spinless baseball). In August, he averaged 2 inches and by September was getting 4 inches.

Likewise, there's a similar dropoff in velocity:

Early in the season, he was throwing his slider around 85-87 MPH, in September this fell to around 83 MPH. So basically he was throwing a slower slider with more vertical break.

But it gets even more categorical than that. Let's look game by game rather than than month by month at the vertical break on his slider:

There's a very clear break line between his first 25 starts, and his last 7 starts, not even the more gradual trend above. The velocity chart doesn't show quite as sharp a change, but there's a change around the same time. This clearly points to some sort of adjustment, it's inconceivable to be a random change. And what was the result?

The spike in his strikeout rate coincided exactly with the change in his slider, driven by a 10% fall in contact rate. Granted, as this chart shows, it wasn't all about his slider, he got more whiffs on all his pitches. Of course, it's quite conceivable a better slider makes everything else play up. We definitely shouldn't expect a 70% contact rate or 30%+ strikeout rate next year, but it does look like Hutchison has a new and improved weapon at his disposal. Nick wrote in October about Hutchison's struggles against lefties and throwing his change-up in particular. Sliders have large platoon splits, so having an average slider is not a great option against opposite handed hitters. But, it may now be a viable option to finish off opposite handed hitters.

Assuming this is a real change, Hutchison looks like a legitimate breakout candidate in 2015 and beyond. The comparison above aside, we shouldn't expect him to be Scherzer, but 3 WAR in 180-200 IP would be reasonable. In fact, I'd suggest looking to extend him now, locking his last 4 control year and maybe a free agent year or option. Of course, it takes two to tango, but Hutchison has already had a significant injury, so beyond able to lock in guaranteed dollars might be very attractive. Either way, another step forward from Hutchison in 2015 would be a nice boost towards playoff contention.

Data and charts from Fangraphs and Brooks Baseball