Nathan: Is "late break" real?

From SABR member Alan Nathan at Baseball Prospectus on March 26, 2013:

Alan Nathan is Professor Emeritus of Physics at the University of Illinois at Urbana-Champaign. After a long career doing things like measuring the electric and magnetic polarizabilities of the proton and studying the quark structure of nucleons, he now devotes his time and effort to the physics of baseball. He maintains an oft-visited website devoted to that subject:

In response to a question posed to me yesterday about late break on a fastball, here is my reply:

I'm not sure I really have much to say about the subject of late break. What I do have to say is summarized in the figure below (click to expand), showing Mariano Rivera throwing his cutter.


The solid curve is the actual trajectory, taken from PITCHf/x data. The dotted curve is a straight line projected from the release direction. The two curves look pretty nearly identical until about 20 feet from home plate, which is just about the point of no return for the batter.

Read the full article here:

This page was last updated March 27, 2013 at 2:16 pm MST.