Can Rick Porcello Regain His Slider?

The Tigers have resigned Anibal Sanchez.  Whether or not you agree that it was a good deal or an over-payment, it does leave the Tigers with six starting pitchers and only five rotation spots.  There are several solutions to this, one being to send Drew Smyly down either in the minors or in the bullpen or even send Rick Porcello to the bullpen for depth.  But the popular opinion around the internet has Rick Porcello being traded and he’s even drawing interest from other clubs.

Porcello didn’t have a terrible year, at least not as bad as his ERA would lead you to believe (4.59 ERA).  His strikeout rate has increased for the 3^rd straight year (5.46 K/9) as well as his ground ball rate (53.2%).  This resulted in a respectable 3.91 FIP and 3.89 xFIP, the lowest totals of his career.  The reason for the high ERA can be attributed to the poor infield defense and his league leading .344 BABIP suggests just that.  However, there was something else that went wrong with Porcello, and that was his slider.  In fact, it was so bad that FanGraphs suggested that he stop throwing that pitch altogether.

So how bad was it?  According to Pitch f/x, hitters teed off of Porcello’s slider with a batting line of .394/.405/.615 last year in 109 AB.  But just one year prior, hitters only hit .227/.268/.313 off of Porcello’s slider in 150 AB and it could be argued that that was his best pitch that year.  So what made it really good in 2011 and very bad in 2012, ignoring small samples for a moment?  One theory is the velocity of that he threw it at.  In 2011, he threw his slider at 75.1-88.5 MPH (averaging 83.2 MPH).  In 2012, he threw it harder at 78.5-90 MPH (averaging 85.1 MPH), an increase of about 2 MPH on average.  The extra velocity flattened the pitch out and made it more hittable. 

If Porcello is unable to regain his slider, he’s basically a fastball/sinker and changeup pitcher and he might be better used out of the bullpen without a third pitch.  But if he is able to get his 2011 slider back (or develop a different 3^rd pitch altogether*) along with his other improvements, he’s primed to have a breakout year next year, especially if he’s traded to a team with better infield defense.  

*Like maybe focusing on his curveball more often?