THE BOOK--Playing The Percentages In Baseball

Thursday, November 01, 2007

Junkballer Pedro

A fantastic look by John Walsh on the transformation of Pedro.  It’s really tough for us to forecast pitchers, because we have no idea was is actual change in approach and what is simply sampling.  Pitchers have so much variability (speed, spin, trajectory, release) as compared to batters (timing, hardness, plane of swing), that pitch by pitch data (scouting data really, in an objective fashion) becomes critical.  If I were running MLB, I’d hire 30 John Walshes, Dan Foxes, Joe Sheehans, Mike Fasts, et al.

What was interesting to me is how consistent Pedro is with his spin effects and speeds on his pitches, other than the curve.  (John calls it “movement”, but it’s really gravity-less movement.  It’s much clearer to think of those numbers as how much spin Pedro is putting on the ball.) Basically, Pedro is able to alter the speed of his pitch a few miles an hour and impart a small but effective change in his spin on the ball so that the batter likely has no idea what the heck his pitches are doing.  (John doesn’t show his release points, but I wouldn’t be surprised if they were all fairly consistent.)

I also think we’re going to be at the point that it doesn’t make sense to call his pitches “fastballs”.  A Jamie Moyer fastball would be a Randy Johnson changeup.  I would much prefer a nomenclature based on all pitchers, rather than to himself.  The nomenclature of the pitch can probably be represented by the spin of the ball.  So, you can have a 87 mph fastball and a 98 mph fastball, if we agree that a fastball is thrown with a certain amount and direction of spin.  So, the “movement” (i.e. spin) numbers that John is showing is what decides what kind of pitch is thrown, irrespective of the speed.  The speed is simply a qualifier to the spin of the pitch.