Checking in on Steven Souza Jr.'s strikeouts and approach

Steven Souza Jr. has been a welcome addition to the power-starved Rays lineup this season, and his .222/.323/.444 slash line is more than acceptable. However, Rays fans can be excused for worrying about his strikeout rate, which was completely out of control to start the year. Pessimists looked at the strikeout rate over 35% and opined that his current production was unsustainable. Optimists yearned for him to cut that number, and to catapult from being a good bat to a great one.

About a month ago, I took a granular look at why Souza was striking out. Souza has had an unusual minor league career path, and the result has been that he's seen less quality pitching than most prospects his age. It therefore makes some sense for him to struggle in his first real taste of the majors. I concluded that despite having a good batting eye overall, there were two specific ways in which he was getting beaten.

1. He swung and and missed too often at breaking balls from right-handed pitchers on the outside of the plate but below the strike zone.
2. He too often took fastballs over the outer third of the plate.

If I could notice these tendencies, you can bet that major league teams could notice them as well, and that major league pitchers could exploit them. Souza had to adjust.

Bring on the Arbitrary Endpoints

The best way to do this would be to look at some rolling 50 PA averages comparing strikeout rate to swing metrics over the past month. If rolling averages are your thing, I know a Rays site for you. But right now I'm just looking for something quick and dirty for this check in, and the FanGraphs splits tab makes it easy to look at monthly totals, so that's what I'm going to use.

Strikeouts stabilize (half signal, half noise) at around 70 plate appearances, so we're looking at a noisy but not completely insignificant sampling here. Souza's June performance is good to see, as a 25% strikeout rate would be acceptable (although lower is always better) for a player with his power. Let's take a look at his approach to see if he's patched the holes that plagued him to start the season.

One of my favorite tools on the internet is Jeff Zimmerman's batter pitch/swing tool at Baseball Heat Maps. The great thing about it is that it allows you to compare a player's performance over a certain time period to either another player, to league average, or to himself over a different time period. I've done that for you with one of the holes in his approach that I previously identified, comparing Souza's approach in the first two months of the season to his approach during the first 18 days of June (I used a 30% regression rate to eliminate small-sample-size stragglers).

A "hot" color means that he has swung at a pitch in that location more often than he had before. A "cool" color means that he has taken a pitch in that location more often. These graphs are from the catcher's perspective.

Here is Souza vs. fastballs from right-handed pitchers (FA, FF, and FT).

Now that's interesting. When I looked before, Souza was aggressive on fastballs on the inner half of the plate but was taking far too many on the outer half for strikes. And immediately we can see that Souza and the Rays have addressed this problem. He appears to be zoning in on that outer third and looking to swing. That may be causing him to take more strikes on the inner third, but, for right now at least, that's a tradeoff I'm happy to see.

The second hole I noticed—breaking balls from left-handed batters below the strike zone on the outer half of the plate—just isn't something that's happened a lot for Souza in June (a month where the Rays have faced a steady diet of left-handed pitchers). On the curves and sliders in that location that he has seen, Souza has swung a little bit more often and missed a little bit less often, but we're dealing with such small numbers (under ten pitches) that there's really no takeaway to be made. Let's put that one in our back pocket for a later date.

Right now though, it's nice to know that it seems like the Rays have in Steven Souza Jr. a hitter who's willing and able to make adjustments as he learns on the big league level.