For years sabermetrics has theorized that pitchers can’t control what happens after a batter strikes a ball. Whether it bloops in for a hit, rockets its way to an outfielder’s glove or lands just inches outside the foul line, it’s a consequence of the batter and the defense, but not the pitcher. That argument is what led to Fielding Independent Pitching (FIP), a statistic that attempts to quantify a pitcher’s performance only for the events for which we know the pitcher has definite responsibility (walks, strikeouts and home runs — in sabermetrics parlance, the “Three True Outcomes”). FIP throws out base hits completely on the basis that they are partially a product of the defense.
But now we have Statcast. The new technology that collects data on the position and velocity of the ball and the players on the field is beginning to change what we know (or thought we knew) about all sorts of things — pitching included. And that’s raising new questions about how much effect a pitcher can have on a ball once it’s put in play. The answer might be: a lot.
But first, let’s talk batters. Last week, I used Statcast to show that harder-struck pitches tend to fall for hits more often. That, generally, makes hard contact good for the hitter and bad for the pitcher. Obviously, some hitters are better at hitting the ball hard. What Statcast tells us is that some pitchers are better at making batters hit the ball softly.
That’s not to say pitchers hold the upper hand. In my models1 of batted ball velocity that incorporate the pitcher, batter and ballpark, the batter’s effect dominates the pitcher’s. A ball’s exit velocity after a bat strikes it is about five times more the batter’s doing than the pitcher’s. This fact seems to partially vindicate FIP — batters really are the ones in control.
At the same time, the pitcher’s effect is not negligible.2 While the best batters increase batted ball velocity by as much as 7-8 mph, the best pitchers suppress it by 1.5 mph compared with the average pitcher.
That has real significance: Such a decrease roughly equates to a 13-point decrease in batting average on balls in play (BABIP) for a given batted ball.3 Over the course of a game, the pitchers who can best decrease exit velocity save about a quarter of a run (on average). A quarter of a run doesn’t sound like much? Multiplied over a season, all those quarters of a run add up to about one win of value.4
So that means FIP is flawed as an overall value metric, at least for some pitchers. Who are those pitchers? Here’s a table of all 485 pitchers with batted ball data this season as of the writing of this article.5 Search for your favorite pitcher and see how many miles per hour he takes away from or adds to the average batted ball.
But now we have Statcast. The new technology that collects data on the position and velocity of the ball and the players on the field is beginning to change what we know (or thought we knew) about all sorts of things — pitching included. And that’s raising new questions about how much effect a pitcher can have on a ball once it’s put in play. The answer might be: a lot.
But first, let’s talk batters. Last week, I used Statcast to show that harder-struck pitches tend to fall for hits more often. That, generally, makes hard contact good for the hitter and bad for the pitcher. Obviously, some hitters are better at hitting the ball hard. What Statcast tells us is that some pitchers are better at making batters hit the ball softly.
That’s not to say pitchers hold the upper hand. In my models1 of batted ball velocity that incorporate the pitcher, batter and ballpark, the batter’s effect dominates the pitcher’s. A ball’s exit velocity after a bat strikes it is about five times more the batter’s doing than the pitcher’s. This fact seems to partially vindicate FIP — batters really are the ones in control.
At the same time, the pitcher’s effect is not negligible.2 While the best batters increase batted ball velocity by as much as 7-8 mph, the best pitchers suppress it by 1.5 mph compared with the average pitcher.
That has real significance: Such a decrease roughly equates to a 13-point decrease in batting average on balls in play (BABIP) for a given batted ball.3 Over the course of a game, the pitchers who can best decrease exit velocity save about a quarter of a run (on average). A quarter of a run doesn’t sound like much? Multiplied over a season, all those quarters of a run add up to about one win of value.4
So that means FIP is flawed as an overall value metric, at least for some pitchers. Who are those pitchers? Here’s a table of all 485 pitchers with batted ball data this season as of the writing of this article.5 Search for your favorite pitcher and see how many miles per hour he takes away from or adds to the average batted ball.
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