Why Is Scuffing The Baseball Useful?

It does not take much to cut, scuff or otherwise mark a baseball. Despite the rules of the game that prohibit such actions, some players actually try to create abrasions on the ball. The reason for this is simple: Scuffing the ball provides an added advantage to the pitcher. That's why baseball umpires routinely inspect baseballs during a game and toss out ones that might have a scuff mark.

Effect on Pitches

As described by Daniel Engber in an article on Slate, a scuffed baseball has the potential to swerve sharply in one direction or another on its way to the plate because of the turbulence created when air passes over the scuffed area. In order to manage this effect, however, the scuffed area must stay on the same side all the way to the plate to create a uniform effect on the air passing over that side of the ball.

Means of Scuffing

Engber also mentions that pitchers have been known to use sharpened belt buckles to scuff the baseball as well as rubbing it along the ground. Major League Baseball pitcher Joe Niekro was actually caught with an emery board and square of sandpaper stuck to his finger to help him add abrasions to the ball. Of course, pitchers aren't the only ones with opportunities to scuff the ball. In fact, catchers might have an easier time of keeping such actions hidden from the umpire.

The Rule

Although pitchers are allowed to use all sorts of grips and motions in their pitching to cause the ball to curve, dive and slide, scuffing the ball is expressly forbidden by the official rules of the game. Simply stated, the section devoted to the pitcher states that pitchers may not deface the ball in anyway. Beyond scuffing, this is meant to include adding any substance to a ball -- commonly referred to as a spit ball -- which might affect the action of the baseball.

Reason For the Rule

George Vecsey's book on baseball history refers to a tragic event in 1920 in which Ray Chapman of the Cleveland Indians was struck in the head with a pitch that ultimately led to his death. That era of baseball allowed the ball to be scuffed and distorted in any number of different ways. In the wake of Chapman's death, however, the rule changed to require umpires to remove balls from the game once they showed signs of scuffing or marking.