Fastball Gains

The introduction of splits here on FanGraphs offers us a wealth of new information as my fellow writers have been expanding upon today. I do not have a post centered around splits today, but instead focused on an area that I continually find incredibly useful here somewhat related to splits: pitch-type breakdowns.

I love pitching and love dissecting its fluctuations from year to year. Tonight, I looked at changes in fastball velocity, both in terms of absolute change and in terms of a percentage over 2008 averages. Changes in average fastball speed do not tell an entire story by themselves, but I think they present several interesting points of fact.

I took a look at all pitchers with at least 50 innings pitched in both 2008 and 2009 and compiled lists of the biggest gains and losses in both fastball speed and fastball frequency. One thing that I found interesting was the seeming lack of relationship between the two. I would have expected pitchers that gained speed in their fastballs to be throwing them more often, but there was little to no correlation between changes in fastball speed and changes in how often pitchers threw fastballs.

Among pitchers with the biggest increases in average speed was Justin Masterson (+2.8 mph), Nick Masset (+2.6), a host of other relievers in the 2.0 range and a few starters mixed in as well, notably Justin Verlander (+2) and, surprisingly, Barry Zito at +1.6. Zito however, had a 5% reduction in percentage of fastballs thrown. Nick Masset was even more dramatic, throwing 15% fewer fastballs.

A top twenty list of increases in fastball speed follows and later tonight, a list of fastball speed drops.

Justin Masterson, 2.8
Nick Masset, 2.6
Matt Capps, 2.1
Ryan Madson, 2.1
Kevin Correia, 2
Justin Verlander, 2
Mark Lowe, 2
Huston Street, 1.7
Barry Zito, 1.6
Brad Penny, 1.6
Josh Johnson, 1.6
Jose Contreras, 1.5
Jon Lester, 1.5
Jonathan Broxton, 1.4
Wandy Rodriguez, 1.3
Luke Hochevar, 1.3
Miguel Batista, 1.3
Chris Volstad, 1.2
Bob Howry, 1.2
Ubaldo Jimenez, 1.2