If the first thing you think about when someone says Noah Syndergaard’s name isn’t his long blonde hair, it’s probably his otherworldly fastball that springs to mind. Among starting pitchers who threw at least 100 innings in 2018, Syndergaard’s average fastball velocity of 97.4 miles per hour ranked second in all of baseball, behind only Luis Severino. And yet, by some measurements it is his slider that has been his most effective pitch against major league hitters. Thor debuted in 2015 but did not fully develop his jaw-dropping slider until 2016, but since then hitters around the league are consistently made to look foolish by the pitch. The following is a table presenting the weighted on-base-average and expected weighted on-base-average of hitters against Syndergaard’s five pitches since 2016, data courtesy of Baseball Savant.
The slider steals the show here and a key contributor to this is the 46.1 Whiff percentage accompanying the pitch, meaning batters are swinging and missing at a Noah Syndergaard slider nearly half of the time he throws it. I have also provided the spray chart of Noah Syndergaard’s slider courtesy of Baseball Savant to better illustrate how he tends to use the pitch. Like most righties, he primarily throws the pitch down and away to the right-handed batter. Yet, while it has been his best pitch, when facing left-handed batters in 2018, he used the pitch far less, throwing it only 12.4 percent of time as compared to the 30.5 percent of the time he threw the pitch against righties. There is, of course, the natural question: Is this the right thing to do? Are left handed hitters better against the pitch than righties? Below is a list of the top 10 starting pitchers by slider usage in 2018, along with Syndergaard (31st in slider usage) with a minimum of 2500 total pitches thrown. I then found how often they used the pitch against right-handed and left-handed hitters, and those hitters xwOBA against each pitchers slider.
Seven of the top 10 slider pitchers see their slider performance drop when throwing the pitch against lefties, which could help explain why every pitcher on this list throws the slider less often against left-handed batters. Noah Syndergaard and a few others, however, seem to be an exception, with the slider performing markedly better against the opposite-handed hitters. I’ll take the time here to note that while he only threw the pitch 160 times against left handed hitters in 2018, his slider was just as successful in 2016 against lefties (.184 xwOBA), when he threw the pitch 209 times. So while the general right-handed pitcher might do well to limit his slider usage against the left-handed hitter, Noah Syndergaard may want to do just the opposite.
It’s not unreasonable to expect that if left-handed hitters see Syndergaard’s slider more often in 2019, they will perform slightly better against the pitch as they are forced to look for it more often. The converse could be said, however, for the pitches he throws less often as a result of increased slider usage. With hitters looking slider more often, they are also bound to be late on one of his deadly fastballs more often. Thus if you assume these affects would roughly cancel out, a back-of-the-napkin style calculation seems to imply that if Thor threw his slider roughly 30 percent of the time against left-handed hitters in 2019, he could see a decrease in xwOBA against by about five to ten points. His xwOBA against in 2018 was .265 (league average is roughly .315) which put him in the top 10 percent of major league pitchers. If a change in pitch mix brought his xwOBA down near .255 he could easily be a Cy Young candidate. For reference, Aaron Nola finished 3rd in National League Cy Young voting just a year ago and finished with an xwOBA of .258.
Featured Photo: Arturo Pardavila III, Flickr