Earlier this week, Arizona Diamondbacks outfielder J.D. Martinez made baseball history, becoming the 18th player to hit four home runs in a game.
Martinez’s accomplishment harkened some people in the baseball community back to a spring training piece written by FanGraphs’ Travis Sawchick, who discussed hitting philosophy with the then-Detroit Tigers outfielder. Martinez’s point, paraphrased (and edited for language) was simple: he’s absolutely trying to hit fly balls, not grounders or even line drives.
The approach makes sense; in 2017, major league hitters own a .242 batting average and .262 slugging percentage—a wRC+ of 28—on ground balls. Those numbers go up rather dramatically to a .251 average, .755 slugging percentage, and 146 wRC+ on balls hit into the air.
It has also helped transform Martinez from a light-hitting, ground-ball machine into one of the game’s most consistent power threats, especially against left-handed pitching. One Colorado Rockies hitter, in particular, has seen a similar increase in productivity thanks to the same type of change in approach.
Charlie Blackmon, from his debut in 2011 through 2014, put up a decent but not great .290/.329/.430 line while hitting a grounder in 42.8 percent of his plate appearances ad maintaining a fly-ball rate of 35.0 percent. But 2015 represented a bit of a transition year for Blackmon; he started to put the ball in the air more and on the ground less, and two years later, he’s blossomed into a star. Over the last three seasons, Blackmon has hit .316/.376/.540 on the back of a diminished 37.6 percent ground-ball rate and an increased fly-ball rate of 37.4 percent.
In Colorado, fly balls are—perhaps obviously—rewarded more than they are elsewhere. This season, hitters have posted a .282 batting average and .819 slugging percentage, good for a 153 wRC+, on balls hit in the air at Coors Field. The Rockies have especially benefitted, hitting .332 while slugging .952, equating to a 184 wRC+. The problem is that the Rockies, with few exceptions, aren’t hitting the ball in the air effectively enough.
Rockies hitters rank fourth-worst in baseball with a fly-ball rate of 33 percent. That’s significantly below the league-average figure of 35.5 percent. Worse, Colorado ranks just 25th in the majors in fly-ball rate at home, meaning they’re not taking advantage of a clear fly-ball hitter’s park (though Coors doesn’t permit nearly as many cheap home runs as people often think, it boasts an expansive outfield that is difficult to cover).
Fewer than half of Rockies players who have accrued 150 or more plate appearances have been league average or better at getting the ball in the air. Blackmon, Nolan Arenado, Mark Reynolds, Trevor Story, and Pat Valaika have succeeded at generating loft in their swings, and for most, there has been a correlation with success. Blackmon, Arenado, and Reynolds should all surpass the 30-homer mark, while Story and Valaika have combined for most of the Rockies’ NL-leading 25 homers from the shortstop position.
Of course, the approach hasn’t always been great for Story in particular. He’s hitting fly balls at only a slightly higher rate than a year ago, but he’s been less successful overall. Several factors are in play there, but a big one is that pitchers have started throwing Story more pitches up in (and out of) the zone, which can negate the success of hitters with his bat path, as referenced in the above-linked article about J.D. Martinez.
Still, even with the low batting average and on-base percentage, Story has—by wRC+, at least—performed as well or better than many of his teammates. The biggest names to consider here are Ian Desmond and Carlos Gonzalez, both of whom have fallen shy of Story’s overall production.
Desmond’s fly-ball rate of 20.2 percent is second-lowest of any regular on the team, ahead of only DJ LeMahieu. It’s a continuation of a trend that began last season, when Desmond’s fly-ball rate dropped from more than 30 percent to the mid 20s. The trouble with that, aside from the fact that flyballs do more damage, especially at Coors Field, is that Desmond is only slightly above average (think Alexi Amarista or Pat Valaika, not Trevor Story or Charlie Blackmon) in terms of sprint speed, according to Statcast. Thus, hitting all those ground balls from the right side—plus having a lower hard-hit rate than a player like LeMahieu—results in some hits (.318 batting average) but no significant damage, as evidenced by the .349 slugging percentage.
Gonzalez, meanwhile, has taken a plunge to 30.8 percent in terms of fly balls. He’s been trending downard in that area for years, but until this year, it’s been leveled out by an increase in line drives. Now, Gonzalez is hitting grounders at a higher rate than he ever has in any full, healthy season and, perhaps not coincidentally, his hard-hit rate is lower than it has been since his rookie year in Oakland.
The good news for CarGo is that, since the beginning of August, he’s hitting the ball in the air at an above-average 36.7 percent clip. The increase in fly balls is one reason why the 31-year-old outfielder has enjoyed a bit of a resurgence over the last six weeks, hitting .320/.400/.515 during that stretch. Whatever adjustments CarGo has made will go a long way toward helping the Rockies hang on to their place in the postseason picture.
The air raid is taking over baseball. The league-wide fly-ball rate has increased steadily since 2012, so much so that pitchers are making adjustments to stay away from the ideal swing planes that are being discovered and implemented by hitters. For the Rockies to truly gain an advantage offensively, especially at their home park, they would be wise to follow suit. There’s no better time for that to start than now, seeing as how the team is on track for its worst season at the plate in 15 years. We just have to hope that they make the adjustment before the cyclical nature of the game takes over and the Rockies find themselves behind the curve.