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The Life of Brian’s Fastball Part 2

Illustrated edition.

Yesterday I talked about San Francisco’s closer Brian Wilson and his breakthrough season. I mostly attributed his recent success to an increase in horizontal movement on his fastball. Since I don’t have my own Pitch F/x database and am to lazy to learn MySQL, I asked our own Dave Allen if he could give me a hand with some Pitch F/x graphs. Dave was suffering with some internet issues and wasn’t able to oblige me until the post had already published, but I thought it would be a shame to not put the graphs to good use. They really bring out the dramatic change in the movement of Wilson’s fastball, and more.



Wilson’s 2008 fastball had the speed of a normal 4-seam fastball, but almost cutter-like movement. This year’s edition is much more 4-seamer’ish. What also stands out his his breaking pitches are a little ‘sharper’, for a lack of a better term.

According to the Pitch F/x data available here at FanGraphs, Wilson’s slider had five and a half inches of horizontal movement last season, and .8 inches of vertical movement. This year’s slider averages 3 inches of horizontal movement and 1.2 inches of vertical movement. I take it that Dave has his own smarter pitch categorization system that differs from straight Pitch F/x, which is why you see more cutters than sliders in Wilson’s 2009 graph.

Whether you want to classify the pitch as a hard slider, cutter or ‘slutter’ or what have you, it’s plain to see Wilson is a bit of a different animal this season.

Thank you Dave.