Bill James recently came up with a system to measure how tired a closer is. It’s a great idea to track something like this but I have two problems with it:
a.) Why just closers? Why not all relievers?
b.) And this is more important, by using a system that bases fatigue on “Batters Faced” an 11 pitch battle is weighted exactly the same as a 1 pitch grounder to SS.
So I took the same system and substituted Batters Faced with Pitches Thrown.
The math if you want to do it is
Pitches (yesterday) x 5/3.82 + Pitches (date-2) x 4/3.82 + Pitches (date-3) x 3/3.82 + Pitches (date-4) x 2/3.82 + Pitches (date-5) x 1/3.82
And thats it. Enjoy.