(Photo by Dan Sanger/Icon Sportswire)
In 2017, swing changers were all the rage. Players started jumping on the trend to start hitting more fly balls to maximize their production at the plate. It has long been proven by multiple people (all of whom are much smarter than I am) that a launch angle between 19 and 26 degrees is where you will find peak production. This reasoning could be found many places but I prefer to refer you to the work of Andrew Perpetua over at FanGraphs. The average MLB launch angle for all players is right around 10 or 11 degrees, so it is natural that as this information starts trending across the internet we have started to see some players buy into the idea that increasing their launch angle will improve their production.
I don’t mean to suggest that internet baseball writers have influenced the game to such a dramatic fashion but at the very least we are realizing this at about the same time players are trending in that direction. Well, these past two years we’ve seen several players start increasing their launch angle such as Yonder Alonso, Matt Carpenter, Whit Merrifield, and Matt Joyce, to name a few. Well, I know it almost seems like an old fad at this point but players are changing all the time. There’s no reason to think players are done adopting this launch angle revolution. I know we are only a few weeks into 2018 but we already have enough batted ball data to start looking at who might be shifting their hitting philosophy.
So I grabbed some quick data of all players with over 300 plate appearances last year and all qualified players in 2018 and sorted by largest decrease in ground ball rate. This is a little bit non-scientific compared to looking at actual average launch angles but for our large-scale purposes, this will be plenty accurate. If a player has made a significant shift in their hitting philosophy or swing mechanics it will show up easily. So let’s take a look.
| Player | 2017 GB% | 2018 GB% | GB% Diff. | 2017 HH% | 2018 HH% |
| Ian Happ | 40.2 | 20.8 | -19.4 | 32.8 | 29.2 |
| Javier Baez | 48.6 | 30.6 | -18.0 | 32.4 | 44.7 |
| Carlos Correa | 47.9 | 31.1 | -16.8 | 39.5 | 26.5 |
| Hunter Pence | 57.2 | 41.2 | -16.0 | 29.4 | 26.5 |
| Mookie Betts | 40.4 | 24.5 | -15.9 | 35.7 | 51.0 |
| Cameron Maybin | 57.7 | 41.9 | -15.8 | 27.4 | 31.3 |
| Matt Kemp | 48.5 | 33.3 | -15.2 | 34.7 | 46.7 |
| Francisco Cervelli | 52.3 | 37.2 | -15.1 | 32.8 | 39.5 |
| Manny Machado | 42.1 | 27.3 | -14.8 | 39.5 | 27.3 |
| Carlos Gomez | 39.1 | 24.4 | -14.7 | 39.0 | 38.1 |
| Dee Gordon | 57.6 | 42.9 | -14.7 | 16.1 | 9.4 |
| Ryan Zimmerman | 46.4 | 34.1 | -12.3 | 40.5 | 46.3 |
| Corey Dickerson | 41.8 | 29.6 | -12.2 | 33.6 | 32.7 |
| Mitch Haniger | 44.0 | 32.5 | -11.5 | 34.7 | 42.5 |
| Carlos Santana | 40.8 | 30.0 | -10.8 | 33.0 | 40.0 |
| Ben Zobrist | 51.1 | 40.5 | -10.6 | 32.3 | 31.6 |
| Jason Heyward | 47.4 | 37.2 | -10.2 | 25.5 | 32.6 |
| Yangervis Solarte | 41.6 | 31.8 | -9.8 | 31.1 | 22.7 |
So with this list, we obviously have a mixed bag of names. Some are older players who aren’t that far off from their career averages (Matt Kemp, Hunter Pence, Ryan Zimmerman, and Ben Zobrist). Then we have Dee Gordon who isn’t ever going to make much of an impact at higher launch angles because he simply doesn’t hit the ball hard enough. As you can see I also included 2017 and 2018 Hard Hit rates. This is to better help us separate out who might be primed to produce more power. An increase in launch angle will help an average power hitter, but it will most help those who already hit the ball hard. Those are the players you can hope to see the largest boosts in home runs. The players from this list that have increased their launch angle AND are hitting the ball hard would be Javier Baez, Mookie Betts, Francisco Cervelli, Carlos Gomez, Mitch Haniger, and Carlos Santana.
All of these players are ones I’d keep a close eye on. They’ve had varying levels of production thus far. You have Mookie Betts who just had a three home run game and then you also have Carlos Santana who is rocking a BABIP under .200. Cervelli interests me since he has always had solid contact numbers but has effectively been a zero in the power department. A boost in home runs could be exactly what he needs to become fantasy relevant. Carlos Gomez is interesting but it is typically his plate discipline that is prohibitive. Judging by his 30% strikeout rate, this is not going to change anytime soon.
Mitch Haniger is also a little interesting to me as his boost in launch angle gets him much closer to his career averages in the minor leagues. 2017 was a mini-breakout for him but it also featured nearly his lowest fly ball rate of his career. Now that he is reducing those ground balls and still hitting the ball hard we might be able to see 30 home runs from him, provided he can stay healthy. Javier Baez interests me as well as he is featuring his lowest strikeout percentage of his career, however, the contact rate is still below 70%. If he could manage to make more contact it would make all the difference for him.
It’s too early yet to know which of these changes are going to hold up as we get more and more data. It is only three weeks into the season and half of these numbers could simply be noise that is gone by the end of the month. For now, I’d keep my eye on these names and see how they maintain their increased launch angle. Batted ball profiles can be quick evidence of a player changing their game for the better.
Great post, Mark. Love it.