The pace of the adjustments has been sudden, with the home run spike beginning in the summer of 2015, the year that began the so-called Statcast Era, when baseball began measuring — and publicly emphasizing — the DNA within every ball in flight: the rate of spin for each pitch, the angle of the hitter’s bat upon contact, the speed at which every batted ball travels.

For the best hitters in the world, more data means a more precise road map from bat to bleachers. And while the proportion of ground balls has essentially held steady — 44.3 percent to 45.3 percent for each year of this decade, according to FanGraphs — hitters seem to know how to drive fly balls with more backspin to make them into homers. The percentage of fly balls that become homers has risen in each of the last four years, from 9.5 percent in 2014 to 13.7 percent this season.

The rapid evolution does not surprise Billy Eppler, the Los Angeles Angels’ general manager.

“It doesn’t, because of something that, actually, Alex Rodriguez told me some years back: ‘If you can articulate what you value, and what you’re looking for, players of this caliber of athleticism can turn themselves into it,’” said Eppler, a former Yankees assistant. “It’s kind of standing the test of time, where guys know that runs are valuable, and the ones that have the capability to do it — meaning the strength — are lifting the ball a little bit more and putting more balls in the seats. But the trade-off that comes with that is contact.”

That’s because the emphasis on home runs creates more holes in hitters’ swings and pitchers are well equipped to exploit them. The most extreme case, perhaps, is San Diego’s Ryan Schimpf, who had 14 homers, and just 12 other hits, to go with 70 strikeouts before his demotion last month.