The Pirates Are Gerrit Cole-ing Corey Dickerson

One of the bigger stories of the early part of the season has been the ace-level emergence of Gerrit Cole. Freed from the Pirates, Cole has moved on to the Astros and seemingly threatened to throw a no-hitter every start. Cole’s strikeout rate has taken off, and one has been left to wonder why this pitcher didn’t show up consistently in Pittsburgh. On the Pirates’ side, Colin Moran and Michael Feliz have been fine. The club has also overachieved, winning more games than it’s lost. But if anything, the Pirates’ early success makes the loss of Cole more painful. No one likes to see a player improve somewhere else.

Something about going to Houston has allowed Cole to tap into his inner potential. There’s been much conversation about why the Pirates couldn’t pull this talent out. As some consolation, however, the Pirates have sort of done a similar thing to the Rays. Near the end of February, the Pirates picked up Corey Dickerson for a song. The Rays, I’m sure, are content with the early performance by C.J. Cron. But the Dickerson of the present doesn’t look like the Dickerson of yesterday. Cole left Pittsburgh and found a new level. Dickerson arrived in Pittsburgh and found a new level. It doesn’t make up for trading an ace, yet there are reasons why the Pirates are firmly in contention.

Even after trading Andrew McCutchen, the Pirates are third in the National League in wRC+, and third in the league in runs scored. It’s been more than a one-man effort — consider, for example, the rejuvenation of Francisco Cervelli. But Dickerson is right there, more than halfway to last year’s full-season WAR. His wRC+ is up, because his average is up, and his on-base percentage is up, and his slugging percentage is up. This has all happened with his BABIP going down. Dickerson has always been a free swinger, and the Pirates haven’t discouraged that — he’s still swinging at more than half of all pitches. What’s important is what those swings have accomplished.

Go back to Gerrit Cole for a second. This year he’s struck out an unbelievable 42% of his opponents. Last year, his rate was 23%, meaning we’re looking at a current improvement of 19 percentage points. That’s an astonishing change for something as otherwise stable as strikeout rate. That’s a number that tends to hang around where it is.

Last year, Corey Dickerson struck out about 24% of the time. The year before that, he struck out about 24% of the time. The year before that, he struck out about 24% of the time. This year? So far this year, Dickerson has struck out about 10% of the time. That’s an improvement of 14 percentage points.

Backing that up, Dickerson’s contact rate on swings is better by more than nine percentage points. There are 185 players who’ve batted at least 100 times in each of the last two seasons. Dickerson owns the second-biggest improvement in strikeout rate, and he owns the single biggest improvement in contact rate. Dickerson is getting the bat on the ball, in an era in which strikeouts are increasingly expected and increasingly forgiven. He’s making contact without sacrificing the rest of his profile.

This plot shows Dickerson’s entire big-league career in rolling 30-game chunks. You can see how his current contact ability stands out.

Dickerson hasn’t been even close to this since early 2014, when there were fewer strikeouts, and when he played in Colorado. We’re seeing a changed player, and that’s because…we’re seeing…a changed player. A shot from 2017:

And from 2018:

Dickerson has seemingly worked to reduce his leg kick, to the point at which it’s sometimes just a toe tap. It’s not quite that simple; Dickerson sometimes still uses a leg kick, and, last year, he sometimes didn’t. But after watching a whole lot of video, the leg kick was certainly more present a year ago. Dickerson is now using it more sparingly, as he keeps his mechanics simpler. Now here’s another shot from 2017:

And from 2018:

This appears to be another part of it. Maybe it’s hard to tell, but in the picture from 2017, Dickerson is holding the bat all the way down at the knob. In the picture from 2018, you can see some bat below the hands. In other words, Dickerson is choked up, and that’s in advance of the first pitch of an at-bat against a non-flamethrower. In certain two-strike situations, Dickerson chokes up even more:

The idea here is pretty easy to understand. This is fundamental baseball: Choking up improves bat control, which improves contact. It can also, in theory, improve selectivity, because the swing is faster, giving the hitter an extra split-second to wait. The downside is that you might sacrifice some power, or you might sacrifice some ability to cover the outer half. If choking up worked well for everyone, everyone would do it. But changes work differently for different players. Joey Votto chokes up almost all the time. From watching video, I know that Dickerson choked up sometimes in 2017, but now he’s doing it much much more, and not only with two strikes. Contact is Dickerson’s priority.

And this has been of by far the greatest help against fastballs. Travis wrote about Dickerson’s fastball problem in February, after the trade. Against heat, and high heat in particular, Dickerson was often getting exposed. This plot of whiff rates should speak for itself.

Dickerson isn’t missing fastballs anymore, not like he did. In terms of contact rate against fastballs, last year Dickerson ranked in the third percentile. He currently ranks in the 77th percentile. Dickerson has shored up that vulnerability, all by simply shortening his swing. His exit velocity hasn’t really suffered. His isolated power hasn’t really suffered. Dickerson just looks better. He’s even played a fine defensive left field, after the Rays had concluded he was probably more of a DH. The Rays saw the traits they didn’t like. The Pirates saw the traits they could work with. Dickerson is probably always going to be an aggressive swinger, but that doesn’t make him a problem by itself.

There have always been change-of-scenery trades. And there have always been trades where one team just likes a given player more than the other one does. The only difference now is that teams are making more data-driven decisions. With Gerrit Cole, the Astros figured they might have an angle the Pirates didn’t realize. And with Corey Dickerson, perhaps the Pirates saw something the Rays didn’t. The Rays designated Dickerson for assignment because he was a player they thought they understood. With all of this newfound contact, Dickerson defies that understanding.