Ok, let’s jump right into this with a couple charts.
First, this is the MLB average wOBA by the three different batted ball types (Line drives, flyballs, ground balls):
Ok, now same chart but with Dansby Swanson’s 2017 numbers added:
I’m sure it jumped off the page for you just like it did me but Dansby Swanson’s wOBA on fly balls in 2017 was 250 points below average. Not 250 points below what a great or good season would be but 250 points below average. TWO-HUNDRED AND FIFTY. There were 252 MLB players who hit at least 50 fly balls in 2017. Swanson ranked 248th out of those 252 in wOBA. What the hell Dansby?
So obviously when I saw this, I had to know why.
First thing I thought was exit velocity. Maybe he doesn’t hit fly balls particularly well. I just did the 2017 batting profiles for the Braves less than a month ago, so from that we know Swanson hits his fly balls with an exit velocity of 89 mph and the MLB average is 91 mph. While Swanson’s number is one full standard deviation below league average, that’s no where near significant enough to explain this kind of disparity in results. After all, Zack Cozart aslo hits his fly balls 89 mph and he had a .513 wOBA on them, more than 300 points higher than Dansby. So that’s not it.
Next logical guess was launch angle. Dansby’s launch angle on fly balls is 38.3 degrees. MLB average is 36.3. That doesn’t seem like a significant difference but in reality it is. The lowest launch angles on fly balls reside around 33 degrees while the highest are right at 40 degrees. So a full two degrees away from average is a big number. Out of the those 252 players, Swanson ranks 237th in launch angle. So we may be onto something here.
But that’s not the whole story, because other guys who had launch angles over 38 degrees included Kris Bryant, Anthony Rizzo, and Justin Turner. And obviously those guys don’t have any trouble producing results.
It could be a combination of the two. Those three guys all hit the ball significantly harder than Swanson does, so they could be getting away with hitting higher while Dansby simply doesn’t have the power to compensate for it. I don’t know. This isn’t a post where I have the answer. This is weird.
And what makes it weirder is all those guys are fly ball hitters. It makes sense that guys who are trying and succeeding at hitting the ball in the air would have higher launch angles because they’re obviously trying to do it. But Dansby is a ground ball hitter. Swanson’s 1.61 GB/FB ratio is one of the highest in the league. A swing that produces ground balls shouldn’t, at least logically, be producing one of the highest launch angles in baseball. And it’s not pop ups. Swanson has a well below league average infield fly ball percentage. Yeah, I don’t know.
Real or Not?
Part of me wants to say this a fluke but looking at his short 2016 stint, it’s the same numbers. 38 degree launch angle and a .235 wOBA on his fly balls. Whatever the reason, this is one of the primary reasons he struggled so badly in 2017. If the average MLB player is getting a .462 wOBA on his fly balls and you’re getting a .211 wOBA, that’s an awful lot of ground to make up and not a lot of ways to do it.
When you look at his profile, the easy thing to say is he needs to hit more fly balls but amazingly, he had a higher wOBA on his ground balls. He does need to keep the ball off the ground more, but maybe more importantly he needs to figure out a way to get more production out of the few times he actually does hit it in the air.
I don’t know how. I’m not sure how realistic it is to ask a guy to lower his launch angle on fly balls a few degrees. That doesn’t seem like the type of info you want to be thinking about while you’re in the box trying to hit major league pitching. There is a simpler option. Weight room. Just hit it harder. Whatever he does, Swanson needs to improve this. We already knew he needed to add more power to his game but if his natural launch angle is going to be among the highest in baseball, an already uphill climb just got tougher.