More than a week into the 2017 season, Steven Souza Jr. is by far the Rays’ hottest hitter. In fact, he’s the 13th hottest hitter in all of baseball with a 223 wRC+. The .370/.485/.593 slash line is eye popping. He’s outproducing perennial sluggers like Mike Trout, Bryce Harper, Josh Donaldson and Paul Goldschmidt.
Yes, it’s a very small sample size, and I’m not here to say this kind of production is sustainable. He’s not going to run an 18.2% walk rate and 9.1% strikeout rate across 162 games.
But I can say is that what he’s done so far when he puts the ball in play is mostly justified in his batted ball profile. In other words, this is not just some crazy lucky streak. He’s getting the production he’s deserved based on how well he’s seeing and hitting the ball.
We can compare Souza to the Fangraphs reference fo average batted ball production. Line drives run a scorching batting average of .685 and a respectable ISO of .190 on average, while groundballs squeak through the defense for a .239 average and almost nonexistent .020 ISO, and flyballs drop in for only a .207 average, but run the highest ISO at .378 because when they do drop in, it’s almost always extra bases.
Getting back to Souza now. That .370/.485/.593 comes with a .391 BABIP. That looks like a pretty high BABIP, and it absolutely is. It will regress. All of this is on 24 balls in play, which is the smallest of small sample sizes and pretty much nothing in the grand scheme of things. But what he’s done so far defends that BABIP almost entirely. The 29.2% line drive rate is by far the highest of his career and carries most of the profile to justifying that BABIP.
Multiplying his line drive, ground ball and fly ball rates by the league average gives us an expected BABIP of .363. That means he’s been lucky for less than 30 points of BABIP.
If you want to see what his slash would look like with the new BABIP, just subtract his strikeout rate from the average and then add the same isolated OBP and power. That gives Steven Souza Jr. a slash of .330/.445/.553. So even after removing the little bit of luck that’s in there, he’s still absolutely killing it at the plate.
In sum: Souza Jr.’s plate approach over this first week plus of baseball has produced more walks, fewer strikeouts, and some impressive results when he makes contact. Even if regression is a given, we can still hope that his early season success represents real progress in his development and can be sustained at some level.