The young Rays’ lefty has taken a step forward in 2018 thanks in part to an improved four-seam fastball.
A common trait some of the most heralded pitching prospects share is that they enter the major leagues with exceptional raw stuff, but unrefined command and control. In these instances it is the development of the latter that determines how close that player can come to reaching his full potential. Clayton Kershaw, for instance, posted double-digit walk rates of 11.1 and 13 percent in his first two seasons. In that third year he dropped it below ten percent, and from there continued to improve as he blossomed into a generational pitching talent. These things can take time.
Blake Snell is in his third big league season. He has gone from posting walk rates of 12.7 and 10.8 percent in those first two years to 7.5 percent this year. I’m not comparing Snell to Kershaw in any way other than to say that this is the road some pitching prospects must travel to find major league success. It takes patience, it takes learning the ins-and-outs of facing major league hitting, and it takes adjustments. Like so many before him, Snell has finally made some adjustments, and he is starting reach the lofty heights that came along with his top prospect pedigree.
Of course it’s not just about walk rate; that’s simply the way of showing his improved control in a macro sense. There are plenty of ways in which Snell has adjusted to become the pitcher that currently owns the 2.40 ERA, 3.31 FIP, and 2.73 DRA that we see today, but when exploring the various aspects of Snell’s improvements, it’s his fastball that has seen the most dramatic improvement in results for the young Rays’ lefty.
There are two primary areas of development for Snell’s four-seam fastball. First, after posting an average velocity in the mid-94 miles per hour in both of the previous two seasons, it has bumped up to 96.2 so far in 2018. Second, while the Rays have certainly been known as a team that encourages it’s pitchers to throw their fastballs up in the zone, Snell has never been able to do that as consistently as he has this year. Check out the heat map of Snell’s four-seam fastball locations from the past three seasons:
Snell certainly tried to keep the ball elevated in the past, but he’s done a tremendous job so far this year of locating the pitch high and on his arm side and keeping it out of the heart, and away from the middle edges of the plate.
Opposing hitters aren’t swinging at Snell’s fastball at a dramatically higher rate; in fact, they are chasing the pitch less and offering at it more often in the zone. But the concentrated placement of the pitch up in the zone is causing batters to make far less contact than they had in the past, so while the swing rate against Snell’s four-seamer is relatively normal, his swinging-strike rate on the pitch has increased significantly from 2017 to 2018.
The increase in whiffs and focus on the upper part of the zone with Snell’s fastball has interestingly enough not been accompanied by an increase in fly-ball percentage on the pitch. Jeff Sullivan of FanGraphs noted this characteristic of the offering after Snell’s first major league start in 2016, and it seems prescient in retrospect:
“One strange thing — generally, when you have a pitcher who works with a rising fastball, that pitcher puts the ball in the air… In the minors, Snell has actually been something of a ground-ball pitcher, which I don’t know how to explain. Maybe hitters beat his other pitches into the ground. Maybe Snell has changed something about himself. What we do know from his record is that he’s long been hard to hit. Just based on his fastball, I’d expect him to be more of a fly-ball pitcher in the majors, but, flies or grounders, Snell will go as far as his control takes him.”
It’s true that Snell was much more of a ground-ball pitcher in the minors, and has become much more of a fly ball pitcher in the majors, trending further towards that end this season. Comparing this year to last, Snell has increased his fly-ball rate by six percentage points and lowered his ground-ball rate by 7.5 percentage points. The wrinkle in those numbers is that they’ve come against Snell’s slider and changeup. His fastball, while more elevated in it’s focus, has essentially maintained it’s career batted-ball profile.
In the vacuum of the “launch angle revolution” that we’ve all been witnessing, an increase in fly-ball rate is not necessarily what you’d want to see. But in 2018, Snell’s hard hit rate on fly ball’s has dropped 9.3 percentage points from 33.8 to 24.5 percent. He seems content to let opposing hitters elevate the ball all they want as long as they’re they’re not hitting it hard. That can be a dangerous recipe if you stop hitting your spots, but Snell’s been executing and it’s been paying off.
According to Baseball Prospectus’ Called Strike Probability metric (CS Prob) — which is in their words, “a proxy for control, or the ability of a pitcher to throw strikes” — Snell is currently enjoying his highest career mark, which squares with what we’re seeing in his zone profile visualizations and with his improvement in walk rate.
A couple of weeks ago, BP’s Russell Carlton warned us against using rate stats and stabilization points to declare a player a player changed, and it’s a point very well made. The season is well over a month old, but in the grand scheme of things the samples are still small. Snell’s mechanics could falter and his fastball could start to catch more of the plate and outcomes would change, which is why we’re not focused so much on the above statistics as we are on the execution. Jeff Sullivan’s words from that early look at the Rays’ southpaw ring prophetic:
“Snell will go as far as his control takes him.”
Blake Snell has harnessed his fastball, is maximizing it’s effectiveness, and appears ready to join the ranks of baseball’s upper echelon starters.
Chris Anders is a featured writer at Beyond the Box Score. You can find him on Twitter @MrChrisAnders.