There was a time when the movement of a pitched baseball was still a very mysterious subject, described by those who played the game only in anecdotal terms. The curve of a curveball was still supposed by some to be nothing but an illusion. The "hop" of a fastball just a trick played on the batter's eye by the stitching. A 1959 article in Popular Mechanics was the first to scientifically explain to the general baseball-watching public that yes, in fact the laws of aerodynamics make perfectly clear that a spinning ball DID actually curve.
We've come a long way since then. Nowadays, anyone interested can search Pitch F/X data and see pretty accurate data on pitcher's release points, the velocity of various pitches, and how much they move from their initial trajectory. The 2015 introduction of MLB's Statcast is now taking this data to the next level.
High-speed cameras and motion tracking are able to tell us many new things about movement on the baseball field. Statcast's initial run has already produced fascinating new data on route efficiency for outfielders, exit velocity off the bat, the speed of baserunners, and, on pitchers' spin rates. While the majority of this data has only been made available to the teams, tantalizing bits of information continue to be released via MLB's website.
Statcast on Verlander and the Tigers' rotation
Anyone familiar with Dan Dickerson's radio partner Jim Price, is familiar with the concept of "late movement". We know what this means in theory. A pitcher with good "stuff" has good late movement, with the ball breaking away from its presumed trajectory well after the hitter has already committed to swinging to the point he expected the ball to arrive at. But why do some pitchers have so much better movement on their pitches than others? The answer as detailed in this recent Statcast article on MLB.com, lies in the amount of spin a given pitcher is able to put on the ball.
|2015||Average Spin Rate|
|Justin Verlander||2,491 rpm|
|Anibal Sanchez||2,383 rpm|
|Jordan Zimmermann||2,313 rpm|
|Daniel Norris||2,385 rpm|
|MLB Average||2,213 rpm|
If you've ever been baffled watching Justin Verlander rifle fastball after fastball right over the bats of a hapless series of hitters, you've got part of your answer right there. It's not just velocity at work. No starting pitcher in the game musters as much spin on the fastball as Verlander is capable of. Sorting through the four-seam spin rates of the top 30 pitchers in the game last year finds only Max Scherzer in Verlander's league in this regard, with an average of 2,486 rpm. Verlander's fastball sizzles through the strike zone in a way that few pitchers in the league can manage.
Knowing now that Verlander ranks among the best in spinning his fastball certainly seems like another point in his favor in terms of being able to remain a highly effective pitcher for years to come. What we don't have, is years' worth of data with which to draw that sort of conclusion with greater certainty. Was Verlander's fastball spinning less due to his weakened state during the 2014 season? You'd have to think so, but there's no way to be certain. Judging by its effectiveness, especially up in the zone to induce whiffs and soft flyballs, this season, it was a lot more than just velocity that returned to his fastball.
The Tigers' starters who rely on a four-seam fastball all have spin rates well above average. What that means is that each is capable of producing late life, and the ability to pitch at the top of the zone to get weak flyballs and pop-ups. Pitchers who don't generate that kind of spin are forced to keep the ball down in the zone to avoid hard contact. Having more juice on the ball allows a pitcher to use more of the strike zone and its edges, giving them more options, and generating more swings and misses than via velocity alone. This is a good thing, and it could be even better next season if the talk about raising the strike zone back to the top of the batter's knees is put into practice.
Statcast is only releasing a limited amount of data at this point. So too much shouldn't be made of the glimpses it provides at this point. It's difficult to do comparisons. A glance at Clayton Kershaw's data, for example, shows a fastball with average life on it. But late movement is only one piece of the puzzle of course. Velocity, arm angle, the ability to locate pitches consistently, deception in delivery, and the pitchers' overall arsenal all play a part in how effective he can be with his fastball. Hitters certainly don't see any of Kershaw's pitches as merely ordinary.
However, the ability to put higher levels of spin on pitches like the fastball, curveball and slider is now a measurable skill, and perhaps, one that isn't diminished over time in the way that velocity typically is. We don't yet know at what point a 95 mph fastball with elite amounts of spin becomes a more difficult pitch to square up than say, a 98 mph fastball. But it's just a fact that a higher spin pitch moves from its initial trajectory more than one with less spin. All other things being equal, it should be more difficult to hit.
And, there are pitches where the reverse is true, and less spin may actually be optimal. The changeup and the sinker, for example, are two pitches most effective when they're dropping rapidly as they approach the zone. Apart from the topspin on a curveball, spin, in most cases, keeps the ball in the air longer.
For Mike Pelfrey's sinker, less spin produces more sinking action, which keeps the ball on the ground and in the ballpark. Pelfrey doesn't have the secondary arsenal to rack up strikeouts and keep hitters off the sinker. But, when it's right, hitters can't do much damage against it either. His mid-90s, sinking two-seamer tumbles in at the lower than average spin rate of 1,884 rpm. Major league average for all two-seam fastballs is 2084 rpm. A high spin two-seamer moves hard to the pitcher's arm side. With low spin, the bottom falls out of the pitch and the hitter has a tough time getting it into the air.
In the case of a changeup, new Tigers' closer Francisco Rodriguez has a changeup that averages just 1,577 rpms, compared to a MLB average of 1,733 rpms. Certainly deception and control play a big part in the effectiveness of K-Rod's changeup, but the lack of spin is a part of why it drops like a stone after the hitter has already committed to swinging.
Statcast and the future of scouting and pitcher performance
What Statcast information signals, is an ongoing revolution in data capture and analysis that is taking place behind the scenes. The implications are far reaching at all levels of the sport.
Where spin rate is concerned, it will be interesting to see how this data affects scouting, for example. Someday this data will be compiled for all minor league teams. Possibly even mobile versions will become available.Teams are likely already using this info to identify undervalued pitchers who have good raw stuff, and are worth working on to improve their command. Capturing this sort of data in bullpen sessions may help an already established pitcher dial in his optimal delivery with each pitch as well.
The eye test is good, Pitch F/X is useful, but combining those with the exact measurements Statcast can provide, is even better. As we begin to make year to year comparisons with this information, fans, coaches and players will all be seeing the "art of pitching" and other elements of the game, in a whole new light.