Jesse Hahn’s Curveball is Educational
If you’ve heard this part or if you just don’t feel like engaging in foreplay, skip ahead. I won’t be upset.
Over the offseason the Padres traded Logan Forsythe, infielder Maxx Tissenbaum and pitchers Matt Andriese, Brad Boxberger and Matt Lollis to Tampa Bay for Alex Torres and Jesse Hahn. Basically, a bunch of spare parts for a good lefty reliever and somewhat of an unknown.
Hahn’s “question mark” status stems from his needing Tommy John surgery in 2010, very shortly after being drafted out of high school, then recovering in 2011, and then not really logging a ton of innings since then. But he started to look pretty sharp last year in limited action.
Now, Torres wears the big funny hat, but since making his MLB Debut on June 3 against the Pirates, Hahn has made the deal look a lot sweeter for the Padres. But more importantly, Jesse Hahn has exposed something interesting about the way the game changes and how going against the current of change can be incredibly useful.
Hahn spots the fastball, sitting at 91, but his curveball stands out when you watch him. It’s an old-school, slow twelve-to-sixer, and it certainly passes the eyeball test as being utterly filthy, inducing a lot of bad looking swings… and misses.
But that’s not all. His change-up, which sits at 83mph, has been extremely effective as well. In order to quantify this, I’ll turn to Fangraphs. They keep track of a metric called wCH/C. In basic terms, this is a park, luck and league adjusted measure of the value of a given change-up expressed in runs above average, per 100 times thrown.
Hahn’s wCH/C of 4.16 would put him well ahead of any qualified starter (if he were one himself), dancing past Felix Hernandez’s 2.83 mark this season. (R.A. Dickey actually leads the league per Fangraphs, but I have my suspicions about how mis-categorization of his pitches might be influencing that result, so I skipped down to Hernandez.)
This extraordinary compliment of off-speed stuff has Hahn striking out 8.6 batters per nine, and has propelled him to a 2.28 ERA, which is slightly outperforming his xFIP (3.39), largely due to a low BABIP (.233) and a high strand rate (80%). But that curveball though!
Watching Jesse Hahn’s curveball is fun, and it sent my mind racing one night. It was as if suddenly all the dots connected.
There is a trend in MLB toward pitches which involve maximum arm speed. That basic package is a 93mph fastball, a hard breaking ball and a change-up. The key to throwing a good slider or changeup? Max arm speed. The split finger is thrown this way as well. I believe this could be giving Jesse Hahn’s curveball an added advantage in two ways.
First, hitters may be less concerned with arm speed. If everything a hitter sees features max arm speed, a hitter can no longer use the speed of the arm to judge what pitch is being thrown, so why should he pay attention to it? If it is increasingly unnecessary for hitters to judge arm speed, this would mean the slower arm Hahn uses to throw his curveball is not being noticed as a dead giveaway like it might have been to hitters in previous eras.
Second, batters are used to a harder breaking ball with a more side-to-side break, as compared with the top-to-bottom shape of Hahn’s offering. The data backs this up:
We can see here that the use of the curve has curtailed since PITCHf/x data started being collected in 2007. We can also see that the curve that is being thrown, is coming in faster, and that the shape of Hahn’s curve is not only markedly more pronounced than the average curveball, it’s even further removed from the shape of the slider, which is the predominant breaker around the league today. Another differentiating factor is that Hahn’s curve averages 74.3mph, as compared with the 77.3mph curveball of the league at large.
The Take Away
All this is to say that Jesse Hahn has a freakish hook, a dandy Charlie, and he locates it well too, but the fact that it’s also different probably contributes to why it’s so effective. Hahn’s curve helps to illustrate the fact that running the opposite direction of a trend can lead to great things. After that thought occurred to me, I watched a start by Odrisamer Despaigne, who is really a complete throwback to the starters I watched as a kid in 1992. I watched him in a different light and I really enjoyed it. Jesse Hahn’s curveball bent the lens through which I watch baseball and I am richer for it.