Rick Porcello’s Latest Tease

Sometimes it’s the things you don’t write that make you look smarter. A few weeks ago, I nearly wrote something celebrating Michael Saunders‘ improved plate discipline. I wasn’t quite feeling it, though, so I went and did something else, and then Saunders embarked on a miserable slump. That’s not the first time something like that has happened. Additionally, there were a few times I wanted to re-visit the Rick Porcello narrative, pointing out that his spring-training strikeouts didn’t lead to regular-season strikeouts. I never wrote anything to that effect, and now Porcello is striking guys out. Again, I look smarter by not looking like an idiot. Over the last 30 days, Porcello’s posted baseball’s third-lowest xFIP. Here’s a selection of strikeout rates over the same span:

• Stephen Strasburg, 27.0%
• Matt Harvey, 26.6%
• Shelby Miller, 26.2%
• Rick Porcello, 26.0%
• Tim Lincecum, 23.9%
• James Shields, 23.7%
• Clayton Kershaw, 20.4%

Tuesday night, Porcello whiffed 11 Pirates over eight innings. That was a career high, besting his previous career high by three. A full 73 times, Porcello has started and struck out three or fewer batters. Porcello didn’t establish a new career high in swinging strikes — for that, we look to May 6, 2012 — but he got plenty, and he generated distinctly un-Porcelloan results.

On April 20, Porcello got torched. Two batters made outs, and nine batters didn’t. To that point, he had three strikeouts in four games. In his next turn, he picked up five strikeouts, but that was against the Braves. In his turn after that, he picked up seven strikeouts, but that was against the Astros. Then the strikeouts kept up, leading through Tuesday. For Rick Porcello, this is new territory. A fairly self-explanatory chart, featuring Jason Marquis:

Porcello’s at 26% strikeouts this May. His May has concluded, presumably. In no other month has he struck out more than 18% of opposing batters. In only five other months has he struck out at least 16% of opposing batters. What we can’t rule out, statistically, is that this is just a fluke. It’s possible. Error bars and everything. But Porcello’s May featured 123 batters. Strikeout rate is a stable stat. This is just asking to be investigated. Rick Porcello’s numbers are different. So, is Rick Porcello different?

The easy joke is that Rick Porcello’s like “**** you defense” after a BABIP-heavy 2012. As a sinker-baller, Porcello’s in a suboptimal situation in Detroit, so he stands to benefit from more strikeouts. Like everyone stands to benefit from more strikeouts. Porcello hasn’t admitted to this, but he also hasn’t said the opposite of this, so the joke lives! And we move on.

In spring training, Porcello picked up 21 strikeouts in 24 innings. This was unlike previous regular season versions of Porcello, and it was also unlike previous spring versions of Porcello, too. At the time, we examined, and we saw that Porcello had all but replaced his slider with a curveball. In the past, Porcello’s slider has let him down, so the curve would give hitters a new look, and it would give Porcello a potential new weapon. We couldn’t just automatically explain everything by pointing to the curve, but Porcello had made a change, perhaps giving his spring numbers a little more substance.

And that’s kept up. Last year, two of every 13 Porcello pitches were sliders, and one of every 27 were curves. This year, one of every 38 have been sliders, and one of every six have been curves. The curve, in other words, has basically replaced the slider, and the slider used to be bad. The curve is slower, giving Porcello greater depth and greater speed variety.

But that isn’t all. And Porcello was throwing the curve in April, when he was considerably less effective. Something happened between April 20 — when Porcello got knocked around — and April 27 — when he didn’t. We turn to Texas Leaguers to examine Porcello’s release points:

Through April 20

Since April 27

Porcello has shifted more toward the first-base side of the rubber, which you can also see in these screenshots:

April 10

May 28

I can’t conclusively prove that this explains Porcello’s turnaround. It’s easy to think of reasons why it might have helped, but it’s also easy to think of reasons why it wouldn’t. This just happens to be a change that correlates to a new level of performance. In the past, Porcello hasn’t often thrown from so far over on the rubber.

Now, importantly, we should look at a split. Porcello has struck out about 14% of lefties. This is more or less on his career average. He’s struck out 24% of righties, which is well above his career average. It’s righties who’ve had the most trouble, and therefore it’s plate appearances against righties we should most closely examine.

Compared to last year, righties have seen a lot more curves, but also a lot more changeups. This is unusual — changeups are thought of as weapons against opposite-handed threats. Righties have gone from seeing 4% changes to 14% changes, and 21% changes in two-strike counts. Porcello’s never done this before, so it seems he has a lot more confidence in his changeup. For the record, this isn’t unprecedented behavior, as Felix Hernandez, for example, throws a ton of changeups to righties, effectively. If it works, it works. General rules don’t have to apply specifically and individually. Porcello, this season, has struck out ten righties with changeups. In all previous seasons combined, he struck out eight righties with changeups. Interestingly, he’s struck out just one righty with a curve. Here’s that curve:

And here’s a righty fishing for a changeup, albeit a pretty bad righty, to be fair:

To summarize:

• Rick Porcello’s strikeouts are way up
• against righties
• especially recently

And there are the following changes:

• fewer sliders
• more curveballs
• more changeups
• shifted over on the rubber

Porcello hasn’t been afraid to throw the change in any count. He’s liked the curve, but just not with the batter ahead. There are changes to Porcello’s numbers, and they’re backed up by changes to his mix and approach. That makes the statistical changes a whole hell of a lot more interesting, because changes without underlying changes are easily dismissed as flukes. What does Porcello’s future now hold in store? That much we can’t know, because teams will adjust to Porcello’s new self, and then Porcello will have to try to adjust back. Right now, he’s kind of unfamiliar, and he’s thriving. But even if Porcello doesn’t keep striking out as many dudes as Matt Harvey, the increased strikeout rate could definitely be legitimate in part. The slider sucked. The curve doesn’t. It’s hard to fake these strikeouts, and with more strikeouts, suddenly Porcello is all the more valuable.

A few months ago, it looked like Porcello could be traded, and in the meantime he was the weak link of the Tigers’ outstanding starting rotation. Now the Tigers have a complete and more outstanding starting rotation. This is why spring-training stats can be fun. This is why baseball can be fun. This is why you don’t take your eyes off a talented 24-year-old, no matter how certain you are he is what he is.