Here’s Your Periodic Update on the Fly-Ball Revolution

This author spent a fair amount of his 2017 documenting the Fly-Ball Revolution. Of the 330 posts this author published from January through the end of last season, 49 included the term “launch angle.” I looked it up. Overkill? Perhaps. But as a devout believer and documenter, I thought it would be irresponsible not to follow up early this season.

In a piece for The Hardball Times Annual this winter, I wondered aloud if the fly-ball revolution would follow the trajectory of shifts. Shifts were a relative curiosity in 2011 and then enjoyed growth rates of 94.8%, 50.4%, 92.2%, 34.8%, and 57.8% from 2012 to -17, jumping from 2,350 shifts in 2011 to 28,130 in 2016. Shifts fell in total volume for the first time last year, to 26,705. The idea and practice of shifting spread dramatically and rapidly. Just about everyone bought in.

Of course, it’s easier to create a defensive shift than to hit a baseball where desired. What each has in common, though, is they challenge convention.

Hitters have changed to a degree. Thanks to Statcast, it’s possible to monitor these changes quite precisely. Major-league batters produced an average launch angle of 10.1 degrees in 2015, of 10.8 degrees in 2016, and of 11.1 degrees this most recent season. In the 2017 postseason, launch angle continued to inch up — to 12.1 degrees, in this case. This spring, Jeff found hitters were lifting even more batted balls in Florida and Arizona.

Early this season, overall launch angle is slightly up (to 11.6 degrees) from last season. And ground-ball rates are down, too — by six-tenths of a percentage point from last season. Ground-ball rates had declined in three straight seasons entering 2018.

So maybe we will not see a shift-like acceleration in adoption at a league-wide level, but it’s probably also much more difficult to implement to such a dramatic degree. Maybe it won’t happen. Pitchers play a part in this, too. What we do know, however, is a lot more players are experimenting and thinking about changing their batted-ball profiles.

I was also curious to see what new adopters might be enjoying some of the intended results to date.

About a year ago to the day, on April 18, 2017, we provided a periodic batted-ball update. In that post, we learned 51 batters had increased their fly-ball rate by two percentage points or more. To date this season, FanGraphs colleague Sean Dolinar found 43.

What we really want to learn as batted-ball totals inch nearer to stabilization rates — 80 balls in play is a benchmark for fly-ball and ground-ball stabilization — is this: who is reducing their ground-ball rates?

The following are the top-50 ground-ball reducers amongst qualified hitters through Thursday:

One of the more interesting fly-ball revolutionaries last year was Lindor, who appears 30th here. While a prospect, Lindor was never thought to have more than 15-homer potential at the major-league level, but he began to make dramatic changes to his batted-ball profile last year and launched 33 homers. Perhaps he was too fly-ball heavy, as his overall offensive efficiency did not spike. (Lindor recorded wRC+ marks of 128, 111, 118, respectively, in 2015, -16, and -17.) Lindor is on the list again.

Jeff has already written about one of the more notable swing-changers in Betts. It’s interesting that the already extreme Trevor Story seems intent on becoming more extreme.

Another interesting name on the list is Baez, ranking as the No. 2 ground-ball changer to date. Cubs manager Joe Maddon said recently that, if Baez could stop chasing breaking balls, he could become Manny Ramirez. That’s really saying something. It also seems pretty unlikely, though Baez has another level to reach with improved discipline. Baez has always had plus-plus power. But Baez needed to do something else to unlock his potential and that was to get more balls into the air to allow his power to play more often. He entered the season with a 1.2 GB/FB ratio for his career and a 1.35 mark last season. Baez is worth keeping an eye on.

Joe Maddon, possibly workshopping new T-shirt ideas after #Cubs get 14 hits and beat #Cardinals: "Keep your launch angles. Keep your exit velocities. Give me a good at-bat."

— Patrick Mooney (@PJ_Mooney) April 19, 2018

Sorry, Joe, but Javier needs to launch.

Span might be up to something, too. Dee Gordon seems like one of the outliers who ought to be trying to get more balls on the ground. I cannot imagine Gordon is intending to hit more balls in the air.

Missing? Eric Hosmer, who has actually increased his ground-ball rate by 4.8 percentage points.

It’s still early. We might need some more time, some more batted balls, to feel confident about rate stats stabilizing at individual and league-wide levels, but the guys on the list are worth keeping an eye upon. They might be up to something.