There’s been a lot of attention paid to a recent article in Baseball Prospectus by Andrew Koo. A free version was later republished by Deadspin.
Citing some persuasive data, Koo argues that Oakland’s Billy Beane may be engaging in “Moneyball” all over again. This time, instead of looking for guys who get on base, Beane is looking for so-called fly-ball hitters: batters who tend to hit significantly more fly balls than ground balls. Koo shows that fly-ball hitters tend to hit ground-ball pitchers very well, and even have a slight advantage over pitchers with no tendency toward generating fly balls or ground balls. By cheaply buying up players whose fly-ball tendencies are otherwise masked by so-so overall production, Beane may have found another discounted advantage over the rest of the league, at least for the time being.
How well does the Brewers lineup rate when it comes to fly ball hitting? According to Koo, they are one of the worst in the league. Here is his chart for plate appearances by fly ball hitters for each club in 2013:
Koo doesn’t specify what he means by a fly-ball hitter, other than to say that means a hitter who generates ground balls at a rate of less than one standard deviation below the league mean. To put the Brewers’ fly ball struggles into context, I tried to derive that number for myself. So, I took all major league players who put at least 80 balls in play in 2013 — which is the level at which Russell Carleton claims a batter’s fly ball / groundball tendency stabilizes — and looked for that cut-off.
By that calculation, a fly-ball hitter in 2013 was anyone with a groundball rate of 39% or less.
With that cleared up, behold the chart of all Brewers who put at least 80 balls in play in 2013, sorted by groundball percentage:
Not a single fly-ball hitter among them, at least as Koo defines it. The closest regulars are Jonathan Lucroy and Carlos Gomez.
Is this something the Brewers should be concerned about? Not necessarily. Every team has its tendencies, and as a general matter, baseball clubs don’t have the luxury of developing any particular tendency in their major league players. Professional baseball players have such a unique skill set, and so few of them end up being successful, that all players have various combinations of attributes. For what it is worth, Baseball Reference says the Brewers were above average in 2013 in the areas of base-stealing, situational hitting, and defensive efficiency. Every team has different skill sets, particularly when considered in the aggregate.
Admittedly, hitting too many ground balls can be a problem. According to Fangraphs, ground balls result in outs, on average, almost three times as often as fly balls do. But the key qualifier there is on average. An average player does not want to hit a ground ball, because if the ball does not leave the infield, there is a good chance an average runner will not make it to first base.
But four of the top five ground-ball hitters for the Brewers in 2013 — Logan Schafer, Ryan Braun, Jean Segura, and Norichika Aoki — were also some of their faster players, and more likely than most to beat out ground balls for hits. In fact, beating out ground balls for base hits was one of the signature aspects of how both Segura and Aoki got on base in 2013. So as always, consider context before jumping to any conclusions about the necessary effect of any player’s batting profile. And, as Koo notes, for all the success the A’s had during the 2013 season beating up on groundball pitchers, once they ran into the Tigers rotation in the playoffs, which does an excellent job against flyball hitters, Beane’s approach once again came up short.
If you do pine for more fly balls in 2014, rest assured you’ll probably get them. The replacement of Aoki, a ground-ball wizard, with Khris Davis will certainly increase the number of balls heading to the outfield, and the returns of both Aramis Ramirez and Ryan Braun from injury should allow them to hit fly balls at a rate closer to their career averages. As far as 2013 went, however, this was one phenomenon for which the Brewers were clearly on the outside, looking in.
Follow Jonathan on Twitter @bachlaw.