Archive - Aug 5, 2009

Soriano by the Pitches

Hoping to understand Alfonso Soriano's hot and cold streaks this year, I turned to the incomparable to break down his present and historical success against different pitches.  The results suggest that Soriano is losing the skill that made him one of the more feared hitters in the game, but that he might have found a method to compensate for this loss.  Below is a chart showing the percentage of fastballs Soriano has seen each year since 2005, with 2009 broken down per month. It also shows his ranking among hitters seeing the fewest fastballs, his "runs above average"  number on fastballs, (wFastball) and how high he ranks among all hitters, and his overall OPS. (As in, not specific to fastballs)  The most important thing to notice here is his wFB rank.

 

Date  Fastball%  FB% Rank  wFastball wFB Rank  OPS
2005  47.9  147/147  27.6  15/147  .821

2006

 54.1  150/159  23.7  25/159  .911
2007  54  150/161  23.3  27/161  .897
2008  53.2  134/145  17.9  38/145  .876
April 2009  45.9  196/197  3.3  55/197  .965

May 2009

 43  185/185  3.6  60/185  .657
June 2009  49.1  180/184  2.4  72/184  .585
July 2009  44.8  190/190  .7  112/190  .992
August 2009  36.7  179/190  -.6  156/190  .220

 

You probably have noticed a couple of striking trends going on here.  First, Soriano has progressively moved from being one of the most effective hitters in baseball against the fastball to being quite pedestrian. Second, pitchers have not noticed and adapted to this change:  They contiue to avoid throwing fastballs to Soriano as if he were the same hitter he was in 2005.  He's not.

So how do we explain Soriano's April and July, when he hit like the hitter for whom the Cubs offered that premium contract?

Finding  that answer requres looking at Soriano's results swinging at sliders.