Luis Castillo Returns For Life Lessons

Last year, I wrote a piece about Luis Castillo. Even though I liked him, the draft helium priced me out of the room. In the process of drooling about his upside, everybody forgot the myriad plausible scenarios in which he could disappoint us. So I wrote about how it could go wrong.

Here we are in 2019, and it’s as if nothing has changed. A painful first half chilled owners, many of whom cut bait. Those with the patience to hold or the perspicacity to buy low were rewarded with a wonderful second half. Castillo is once again among the most heavily hyped non-ace pitchers in the league.

Today, we’re going to revisit that post, using the classic internet technique of quote – respond. You’ll see what I mean.

Let’s just get this out of the way. I really like Luis Castillo. I like him for all the reasons Jeff Sullivan and Nick Pollack also really like Castillo (Sullivan’s post, Pollack’s post). I emphasize my ‘like’ of Castillo because the rest of this post is about his downside; all the various scenarios in which Castillo isn’t the shiny bauble we witnessed late last season.

I still really like Castillo.

The real world has repeatedly confirmed that humans are really shitty at thinking probabilistically. NBC’s Craig Calcaterra was discussing this very topic earlier today with regard to politics. Remember when Nate Silver predicted Hillary Clinton would win with something around a 75 percent likelihood? That meant a Trump victory had the same odds as flipping a coin heads up twice in a row. That happens a lot. In fact, it happens one quarter of the time. Silver wasn’t wrong – at least, we can’t know that he was wrong without a LOT more data. A Trump victory was well within the realm of possibility.

Perhaps I should have left politics out of this. It’s a good example though. A 75 percent chance feels very high. Flipping heads twice in a row (the 25 percent outcome) isn’t very hard.

The Castillo painted by Sullivan, Pollack, and others may be here to stay. He existed for a time in 2017. Performing at a high level is a great indicator for future ability to perform at a high level. Still, we as an industry are getting a little crazy about 89.1 good innings. Here’s how it could all go wrong with my guestimated risks. Adjust those however you wish.

Now we have 171.1 good innings and 82.2 bad innings.

Injury – 35 percent

Every pitcher from Clayton Kershaw to the shambling corpse of James Shields has a similar injury risk. A few positive outliers might be closer to a 25 percent risk. Some oft-injured guys could be as high as a 75 percent risk. For young, hard throwers, the risk is probably slightly above the rest of the population. Do note, Castillo averages 97.5 mph as a starter. That puts some strain on important joints.

The injury scenario includes a wide range of fantasy outcomes. A serious injury – see Alex Reyes – could torpedo his season before it even begins. A less serious injury – see Kershaw – may simply mean fewer high quality innings. Many minor injuries lead to inconsistent performance – especially for pitchers who aren’t used to working without their best stuff.

Shields recovered some balance in his shambles. Poor Kershaw followed my instructions a tad too closely. Castillo did not miss any time to injury.

What We “Know” Isn’t True – 15 percent

Based on his first taste of the majors, we think we know a few things about Castillo. For instance, he appears to be a hard throwing ground ball pitcher with a high whiff rate and plus command. What if his velocity declines a tick or two? What if he’s not actually a ground ball pitcher? After all, he did post a 39 percent ground ball rate in 94.1 Double-A innings. What if his command evaporates? What if hitters learn to anticipate his offerings – i.e. the scouting report catches up? What if he loses feel for an offspeed offering?

Yeah, that’s a list of clumsy hypotheticals. We could keep going. Individually, they’re all quite unlikely to be true. However, just as bundling a bunch of bad credit loans together can make a (usually) reliable financial asset, if you consider enough improbable negative scenarios at the same time, it starts to become increasingly probable that at least one of them happens.

Well, here we have something. We didn’t know Castillo as well as we thought. He was missing a couple ticks on his fastball early in the season. He didn’t quite recover all of it in the second half, although a one mph improvement was apparently enough. His walk rate was nearly twice as high in the first half as in the second half. His ground ball rate fell from nearly 59 percent in 2017 to 46 percent last season. It didn’t show any signs of returning. Meanwhile, his over-17 percent HR/FB ratio remained intact.

From this, we can intuit that the command ranges from average to plus. There’s reason to hope he’ll kick off 2019 on the upper end of the scale, but we shouldn’t be shocked if he walks more than 3.00 BB/9. He should no longer be viewed as a ground ball pitcher – we were wrong.

Castillo reaps most of his positive results via an excellent changeup. His two fastballs feature below average outcomes although they played up in the second half after terrible first half outcomes. Perhaps his results are very sensitive to velocity or modest changes in command. The slider isn’t particularly good. Or bad. It’s just a thing he also throws.

Fluky Bad Luck – <5 percent

Over the course of a full season, consistently fluky bad luck isn’t all that common. But consider this. His home is Great American Ballpark – the place Scooter Gennett hit four home runs. Daniel Nava popped two there. The Reds will play nine at Miller Park. They’ll visit some other hitter parks. Over half his starts will be at a very homer friendly venue. Despite his high ground ball rate, Castillo was touched for 1.11 HR/9. Ground ball pitchers sometimes have “true” HR/FB rates around 15 percent. A little bad luck with sequencing of events could fuel some ERA pain.

For Castillo, his frequently used four seam fastball was his hittable offering. Perhaps he’ll reduce his heater usage in favor of more sinkers. Maybe that will work. Maybe it won’t.

At this point, the main piece of “luck” we’re waiting on is his HR/FB ratio. If he ever gets that under control, he could be some kind of fresh, right-handed Cole Hamels with a strikeout per inning, low walk rates, and around a 3.20 ERA.

Ominously, almost nothing changed about Castillo’s batted ball outcomes or plate discipline data between his two divergent half seasons. I’m left to wonder if we’re falling for a different kind of “fluky.” Could first and second half Castillo be the same guy?

We hoped you liked reading Luis Castillo Returns For Life Lessons by Brad Johnson!

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Tristan
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Tristan

Super interesting dissection, Brad. It’s easy to see why so many can believe he’s ready to take a step forward. One wonders if he might need to develop that breaking ball to truly arrive as an ace, though. One other factor – he seemed to improve somewhat after the coaching changes in Cincinnati last year. Not sure if that’s related, but will be interesting to watch him under a new pitching coach and a manager with a background in player development.