Domonic Brown had a May for the ages, hitting .303/.303/.688 with 12 homers and 25 RBI. He looks like the prototypical post-hyper, a guy who finally fulfills his potential after years of disappointment. Now is a great time to compare Brown's current stats to last year's, since his games played and plate appearances are essentially in line with each other. And when doing so, we see a major change in one stat. So is that change a sign of newfound power or an unsustainable surge? Let's explore.
In 2012, Brown had 212 plate appearances in 56 games. Through June 8, he's had 228 plate appearances in 59 games this season. He's actually striking out a bit more and walking way less this season, but since we're considering his home runs, we're a lot more interested in his batted ball stats:
2012: Ground-ball rate: 46.5 percent, fly-ball rate: 32.9 percent, line-drive rate: 20.6 percent, ground ball/fly ball: 1.41
2013: Ground-ball rate: 45.3 percent, fly-ball rate: 33.1 percent, line-drive rate: 21.5 percent, ground ball/fly ball: 1.37
Those numbers are eerily similar, and suggest a player who hasn't really changed all that much. However, Brown's home-run/fly-ball ratio, the percentage of fly balls he hits that leave the park, is an insane 31.6 percent. To put that in context: The last time someone topped 30 percent for a full season was in 2008 when Ryan Howard led the league with 48 homers and a 31.8 percent HR/FB ratio. Last year, Brown's HR/FB ratio was a measly 9.8 percent. So, again, is this indicative of Brown jumping a level or two in power, or did he just have a ridiculously hot May? To answer that question, we'll have to delve a little deeper into HR/FB.
HR/FB does a great job of telling us how powerful a player has been. In terms of pure power, it actually probably does a better job of measuring power than home runs do. That's because some powerful hitters also hit a ton of line drives, which tend to stay in the yard. Is a guy who hits 30 homers and 25 doubles absolutely a better power hitter than someone who hits 20 homers and 40 doubles? Not necessarily, and the guy with fewer homers but more doubles likely has the superior HR/FB ratio.
However, we can't look at HR/FB ratio in a vacuum. It's important to consider it along with ground-ball rate, fly-ball rate and line-drive rate. Why ground-ball rate and line-drive rate? Well, if a player experiences a major dip in home runs, but has the same HR/FB rate, his line-drive rate or ground-ball rate necessarily increased. If his line-drive rate increased, chances are he became a more effective hitter as a whole. If his ground-ball rate increased, his numbers probably suffered as a whole. But while the entirety of a hitter's batted ball stats is important, fly-ball rate clearly carries the most weight here. If a player's HR/FB ratio jumps, but his fly-ball rate drops, he's probably no more powerful than he used to be. He's just hitting fewer fly balls. If a player experiences the inverse, it's a sign that he's losing power. If a player's HR/FB increases and his fly-ball rate remains flat, as is the case with Brown this year, it's highly suggestive of a player who has found a new power stroke.
What does this mean for Brown and his fantasy owners for the rest of the season? Well, he looks like the true post-hyper, come to life. HR/FB ratio increases like this simply don't happen without a reason. We heard a lot about Brown's revamped swing during spring training, and it appears to be paying off. The Phillies desperately needed some youth to carry them forward. It looks like Brown will lead that charge.