Staying ahead means plenty of tinkering for pitchers

To stay ahead of hitters, Zack Greinke's array of pitches is a work in progress.

Ralph Freso/AP

Over the course of a career, every starting pitcher has to deal with change. As the velocity on their pitches wanes or the league figures out what they throw, they have to continually adapt; feature secondary pitches more often, develop new pitches, add wrinkles to old pitches, or mix up their pitch selections to keep hitters off balance. If you want to get 600 outs per year, every year, you can’t do the same thing every time out.

For Zack Greinke, much of that story of adaptation revolves around his slider.

There were the heady times, of course. The 2009 season with Kansas City brought a Cy Young Award. His slider? "It was amazing, the best pitch I ever had," Greinke said before a game with the Giants last week. That pitch was a big part of how he posted a 2.16 ERA and struck out 242 batters.

Unfortunately, time comes for all pitchers. For Greinke, he saw it in the slider. The pitch "slowly got a little worse," Greinke said — it was "coming out real good, but the hitters weren’t really reacting to it." Why? Greinke shrugged. That 2009 slider "was just better, it just happens." Watch the rates on the pitch drop:

In 2010, then-teammate Brian Bannister was a proponent of sabermetrics. Greinke took to it, famously telling Tyler Kepner that he tried to keep his FIP as low as possible. That meant focusing on strikeouts, walks and homers — sometimes trying to coax fly balls in Kauffman’s large confines, and then later trying to get a lot of ground balls in Milwaukee’s launching pad.

The ground-ball approach didn’t lead to his best seasons. "They weren’t soft grounders, they were well-hit ground balls, they were getting hit really hard" Greinke said of the grounders in Milwaukee. Between 2008 and 2010, hitters never managed a 20% line-drive rate against him. In Milwaukee, they had a 22% line-drive rate (21% is average). In a related matter: "I don’t really try to get ground balls any more."


But there was something else going on, specifically with his slider. Greinke started experimenting with a cutter in 2010 and 2011. "That might have messed with the slider," said the Dodgers pitcher. "Whenever you throw two similar pitches, they end up meshing."

Greinke thought most pitchers trying to throw the cutter and slider would run into this problem. The grips are too similar, the movement and mechanics start blending. When you take a look at the league overall, it turns out Greinke is correct. To create the table below, I looked at the 30 pitchers who most often use each off-speed pitch and then looked at which other off-speed pitches they also featured. You can see that the slider/cutter pairing is one of the rarest in baseball, even within the group of pitches that break the same general direction:

Back to Greinke — his excellent slider and meh cutter, when put together, "became two average pitches." The numbers seem to agree. Check out the difference in velocity and movement on the slider before and after he started experimenting with the cutter. In 2009, the pitch went 85.7 mph and moved 3.6 inches horizontally and 0.6 inches vertically.

Some of this change to Greinke’s slider — more horizontal movement and less vertical movement — is maybe permanent. "I switched the grip on my slider, so the spin off my fingers is different than it used to be," he admitted. But now that the cutter is out of the arsenal, the slider is ready to rock. His reach, swing, and swinging strike rates on his feature pitch are all up significantly in the early going this year.

And in the meantime, the rest of Greinke’s arsenal has matured. Take the change-up; he’s thrown it his whole career, but it hasn’t been the same pitch. "It was an awful pitch, they just wanted me to work on it," the pitcher said of the Royals’ coaching staff. "It’s been bad for a long time." But the hard work is paying off ("Every year it gets a little better"): the average change gets 15% whiffs, and Greinke’s change managed that last year for the first time in his career, after years of hovering around 10%. That number jumps to 17% against lefties — "It’s probably my best pitch to lefties now," Greinke agrees.

The pitcher has also changed his mind a bit about pitching to FIP these days. Back when he thought about the stat more often, he noticed something: "I kept having good FIP and xFIP but my actual ERA was higher than those numbers."

The three-year stretch between 2010 and 2012 is the only stretch of his career where that was true. Sometime in August of 2012, Greinke had enough: "I’m done trying to pitch to that stuff, I’m just going to try and get outs."

What has that meant? It’s meant a few more changes and curves as he’s willing to trade weak contact for swinging strikes. It’s meant, perhaps unconsciously, a slight return to pitching further down in the zone. It’s meant tinkering with and then scrapping the cutter.

It’s all the things that a pitcher has to do when he’s faced with change in his pitching mix.


When your slider doesn’t get the same reactions that it used to, "you have to come up with why it’s happening and try to mix something else in," as Zack Greinke put it.