“To stand still is to fall behind.” -Mark Twain
The quality of baseball has improved tremendously over the past few decades. The ballplayers your grandparents watched spent the offseason working second jobs. Nowadays, the players spend their winters exercising and looking for ways to improve their games. As a result, the overall skill of the players improves incrementally each year.
This isn’t easy to observe in the moment— the batting, pitching, defending, and baserunning all improves at about the same rate— but over the generations the difference is very real. The fastballs are faster, the launch angles are higher, and the defensive positioning is smarter.
While each player works to improve in some capacity, the differences vary. Some pitchers try to improve command or get in better shape, while others learn new pitches. Now that we’re a month into the 2019 season, we can look at which pitchers picked up something new in their arsenals.
There are 65 starting pitchers who threw at least 100 innings last season and at least one inning per team game in 2019. Additionally, there are 99 relievers who qualified both this year and last year. Using Pitch Info data (found on FanGraphs), we can examine which of these pitchers are throwing a lot more or less of seven types of pitches: fastballs, cutters, splitters, sinkers, changeups, sliders, and curveballs.
This article will look into some of the more interesting trends. If you want to view the spreadsheet with all the raw data, click here.
Fastballs and sinkers
Two pitches are declining in usage league-wide: four-seam fastballs and sinkers (two-seam fastballs). Starting pitchers are throwing 0.4 percent fewer fastballs and 1.8 percent fewer sinkers. Relievers are using 1.8 percent fewer fastballs and 1.6 percent fewer sinkers. These don’t seem like huge numbers, but across the entire league they represent significant differences.
This supports information we have that these two pitches are less effective than previously thought. Batters tend to hit fastballs better than other pitches. The Yankees have gained notoriety for discouraging their pitchers from throwing fastballs. Baseball Prospectus’ Matt Trueblood published work detailing the relative ineffectiveness of sinkers, and our own Kenny Kelly noted four pitchers who improved by ditching the pitch.
However, several of the pitchers who have reduced their fastball usage the most have increased sinker usage, and vice versa. Stephen Strasburg and José Quintana are tied for the second highest fastball usage decline with 15.8 percent. (Ivan Nova is first with 17.6 percent.) It just so happens that they lead MLB with the most increased sinker usage: Strasburg with 14.3 percent and Quintana 12.7.
The same is true in reverse. No starting pitcher has increased his fastball usage more than Andrew Cashner (17.4 percent), and he leads baseball with 28.1 percent sinker decline. The top six fastball increasers all reduced sinker usage by at least 8.3 percent.
The same is true for relievers, where the top three fastball increasers all decreased sinker usage by at least 11.7 percent. David Hernandez has made the most drastic change, throwing his fastball 25.8 percent more and his sinker 28.7 percent less.
Similarly, the top three sinker-increasing relievers all decreased fastball usage at least 17.8 percent. José Álvarez is the main culprit, using 16.9 percent more sinkers and 17.8 percent fewer fastballs.
Cutters and sliders
Time for a disclaimer on pitch categorization: it’s far from exact, and there’s room for interpretation. Take a look at this pitch from Zach Eflin:
It’s best described as a slider. Pitcher List certainly thinks so. However, according to Pitch Info, Eflin doesn’t really throw a slider anymore. He went from 22.7 percent slider usage in 2018 to just 3.5 percent this season. Meanwhile, he leads all of baseball with a 32.2 percent cutter increase.
Baseball Savant disagrees. They don’t believe Eflin throws a cutter at all, but claim his slider usage outpaces any other pitch. It’s hard to say which is correct. Sliders and cutters are both thrown hard with a horizontal tail. Generally, a cutter is supposed to be a little faster with more subtle break than a slider, but there’s plenty of gray area. Jonathan Papelbon used to throw a cross between a slider and a cutter (with a crass nickname).
There’s no gray area with Iván Nova though. He developed a new pitch this season that he didn’t throw at all last year. Pitch Info calls it a slider, whereas Baseball Savant thinks it’s a cutter. Regardless of the name, he’s using it 19.6 percent of the time at the expense of his fastball. Given his 8.42 ERA, this would appear to be a mistake, but there’s reason to hope. He yields a .138 xwOBA on the new pitch; it’s his preexisting offerings that have been getting crushed. Besides, his 101 FIP- suggests he’s been pretty unlucky.
In the bullpen, Drew Steckenrider threw fastballs almost exclusively in 2018. Now, he mixes in a slider 35.5 percent of the time. Much like Nova, the results haven’t worked in his favor, with an ERA of 7.15 and xSLG of .588.
Taylor Rogers is taking “sinker/slider” to whole new extreme. He introduced the slider last year, throwing it 13.2 percent of the time. Now it accounts for 46.7 percent of his pitches, having nearly scrapped his curveball and fastball altogether. Despite the change in approach, he’s having a similar season to last year by both traditional and Statcast metrics.
Curves, changeups, and splitters
Not too many pitchers have shown drastic differences using other pitches, but there are a handful of note. Reigning AL Cy Young winner Blake Snell apparently thought his repertoire required tweaking. He leads all starting pitchers with a 13.2 percent curveball increase, throwing his fastball 8.6 percent less. Matt Barnes made a similar change in the bullpen, throwing 16.1 percent fewer fastballs and 17.5 percent more curves.
Andrew Cashner leads MLB starters in pitch increase for two different pitches: changeups and fastballs. Despite the drastically changed approach, the results are pretty much the same. His FIP dropped a little from 5.32 to 5.11, while his strikeout rate mostly stagnated (14.5 percent in 2018, 14.7 percent this year).
There are only two starting pitchers who consistently feature splitters anymore: Kevin Gausman and Masahiro Tanaka. Gausman is trying to make up for the rest of the league, though. He increased his his usage of the pitch by 12.1 percent.
Making a difference?
No two pitchers throw the exact same type of pitch. German Márquez is a right-handed starting pitcher for the Rockies, and Scott Oberg is a right-handed reliever for the same team. The former averages 86.1 mph on his slider, while the latter averages 85.5. In theory, they should be pretty similar.
Here’s Márquez’s slider:
And here’s Oberg’s:
There are subtle differences, but those differences are enough to make them totally distinct to a batter who may face them both in the same game.
It’s unimaginably difficult to hit anything a major league pitcher throws. When pitchers feature something new or dramatically change their usage, they really ought to see an uptick in strikeouts... except they don’t. How can any batter expect to see something from a pitcher, get something totally different, and hit it anyway? It’s incomprehensible, but somehow they do it!
While it’s not linear, the league-wide trend of pitch usage always signifies better pitching. If a pitcher scraps a slider for a curveball, for example, it’s probably because it makes them better at their job. Yet, we aren’t seeing better pitching numbers every year. Apparently, the hitters must be improving, too.
Daniel R. Epstein is an elementary special education teacher and president of the Somerset County Education Association. In addition to BtBS, he writes at www.OffTheBenchBaseball.com. Tweets @depstein1983