Who has the Best Slider in Baseball?

- By Troy Patterson

When trying to find the best type of any pitch the systems to find it have changed. In previous generation you spoke poetically about your favorite pitcher and his nasty curve or filthy heat and the discussion was all left to interpretation. Now with the plethora of data like pitch f/x, pitch values and advanced stats there can be real reason to believe you might know who’s best.

The first place to begin looking for the best pitch of any type is pitch values. Using Fangraphs.com to rank pitchers by slider pitch values in both the standard ranking and pitch f/x version the number one pitcher by a long shot is Tommy Hanson. In 2012 his slider has been worth 11.8 runs to the Braves*.

*Pitch values tell you how many runs the player saved for their team compared to average. A negative value means the pitch was worse than average and cost his team runs.

That value of 11.8 though is deceiving as Hanson throws a lot of sliders and perhaps he’s just totaled more runs that way. To solve this we take the pitch value per 100 pitches. In 2012 Hanson has a 3.44 pitch value per 100 sliders. That ranks him fifth among pitchers in slider value per 100 pitches.

So if he ranks fifth he must not be the best, but using the per 100 value this early in the season can cause some pitchers to artificially inflate their numbers. Here are the itchers located above Hanson in 2012; Kyle Drabek, Trevor Cahill, Brandon McCarthy and Phil Hughes. None of these pitchers have thrown the slider more than 7 percent and have likely seen the influence of small sample size.

On the other hand Hanson has not only been stellar this year, but his slider has been among the three best sliders since he reached the majors in 2009. Only Clayton Kershaw and Ervin Santana have had a better total value on their slider since then within a few runs.

This season though Hanson has had the clear and away best slider with only Ryan Dempster close with an eight. While his slider has been devastating this season it really hasn’t changed since last season.

His velocity dropped in 2011, but this season it has held the same. His slider movement has changed and the combined effect has been better so far although some disagree it will keep up . Since that article though he is still dominating and the swing rate on sliders has risen to career levels. It seems more like the small sample was influencing the numbers.

Here is a graph of his 2011 movement:

The green dots are his sliders and the average is a fairly flat vertical movement and the horizontal movement is toward left-handers. This season has been slightly different as seen below:

Notice that his slider is no longer centered on the 0 for vertical movement, but with the same horizontal movement. This change isn’t large, but so far it has been effective. The biggest change appears to be something Hanson can’t control. Through 298 sliders thrown this season Hanson has yet to give up a home run. In his career his slider has given up a home run on 4 percent of fly balls and line drives.

Hanson has company at the top, but 2012 he has started to show what might be the best slider currently in baseball. He’s able to use it 30 percent of his pitches and dominate hitters. It’ll be interesting to see where he stands at the end of 2012, but it should be fun comparing Kershaw’s and Hanson’s slider for years to come.