Matt Carpenter IV

In my very first article for this site, I wrote on the history of Matt Carpenter as a full time player, documenting the extreme differences in his profile from year to year. In 2013, Matt had above average patience, and very little home run power, but was a line drive machine who racked up hits and doubles at extraordinary rates. In 2014 he took his already patient tendencies to the absolute extreme, posting the sixth best walk rate in the league despite a complete lack of power numbers to cause pitchers to pitch around him. He did it by swinging at the least pitches out of the zone, and the least amount of pitches in the zone just to top it off.

2015 was the best version of Carpenter yet, if we ignore his inflated BABIP in 2013. He was the second-best player in the league at avoiding ground balls, and higher aggression in the zone allowed him to tap in to his power, finally posting strong HR/FB (home run per fly ball) and ISO (isolated slugging) rates. Carpenter wasn't as patient as he was in 2014, but only dropped from sixth to fifteenth in the league in walk rate, due to pitchers being more careful not to give Marp something to drive.

Going into the season we were told that Matt would be attempting to take the best of each of those profiles and combine them into one, which would be quite the feat. How's he been doing with that so far? Here's his latest season, presented with his three other full seasons for comparison:

Like the previous post referenced, along side each of the four core stats, I've conjured a "+" stat which adjusts each stat to league average (but doesn't adjust for park, contrary to most other "+" stats) followed by Matt's rank among qualified players in that stat. For consistency and simplicity, each is ranked by highest quantity even if having less is a good thing.

The overall wRC+ isn't great, but it's held down by some short sample variance with his BABIP (batting average on balls in play). Things would seem to be going well besides that, with a nearly identical league adjusted walk rate from last year to go along with cutting down the strikeouts that got on some people's nerves last year. His ISO is a bit lower than last year's, but will take much longer than K and BB rates to stabilize.  And if not for getting robbed by Billy Hamilton, his ISO would stand at .269, much higher than last year anyway. With most these surface stats we want to keep in mind that there's still a lot of noise abound.

Let's dig deeper though, starting with the plate discipline numbers:

Carpenter thus far has a slightly lower O-Swing rate (percent of pitches outside of the zone that he has swung at) than he did last year, but league average this year has dropped a farther distance, explaining why his league adjust O-Swing has rose a little. But by a corresponding amount, he's also been more aggressive in the zone. Carpenter has yet to swing at pitches at an above average rate, but he's been getting closer. So far, pitchers are avoiding the zone much more with Carpenter than they have, with one of the lowest Zone% in the league. He's also raised his contact rate a bit.

These are short samples, but plate discipline stats do stabilize quicker, as they represent clear choices by the hitter or pitcher. Carpenter has seen 301 pitches so far this year, so for instance the difference in Z-Swing% (percentage of pitches in the zone swung at) is 9 swings more than expected based on last year. That's less than one extra swing a game, but that's not nothing. The difference in Zone% amounts to just four pitches though, so perhaps that's not something to pay attention to too much at this point.

One thing that interests me about 2016 is that it is so far Marp's best season in terms of strike zone judgement. I've seen a metric used elsewhere for quantifying this: They take the percentage of overall pitches that were either (a) out of the zone and not swung at or (b) in the zone and swung at. I believe it is called Correct%, and if not well that's what I'm calling it for today. The formula goes:

Correct% = ((Zone%) x (Z-Swing%)) + ((1 - Zone%) x (1 - O-Swing%))

And here's how Carpenter has fared at the stat in his full-time seasons:

Interesting that this  reveals that while the 2014 Carpenter may have been super-patient, it didn't mean he was practicing strong strike zone management, in fact that high rate of pitches in the zone he took meant it was his worst season in this metric. Of course, I think Marp is smart to take as many borderline strikes as he does early in the count, as you can't do much with a pitch right on the edge of the plate and it might get called a ball anyway. But it looks pretty apparent that Carpenter knows that even last year he was passing up too many good pitches to hit, and he's starting to find a way to get a few more swings on hittable pitches. That's speculation, but it would also be him building on what he consciously attempted and succeeded in doing last year as well. At a 2% bump he's only guessed right on six more pitches than the rate expected from last year, but it's eighteen more than 2014's rate, so overall this project is going in the right direction.

Lastly, and I guess least too because they're more affected by the short sample of it still being April, here's Marp's batted ball stats:

The line drive percentage is down, but LD% is pretty noisy compared to it's counterparts FB% and GB%. The GB% spike from last year is a bit concerning as part of what made Carpenter the 2015 version so success is an elite low GB%. He's had 42 balls in play thus far, making for two and half more ground balls than expected based on last year. That highlights pretty well how noisy these numbers still are at this point, but it still gives us something to watch for as the season progresses. One great sign: Matt is hitting the ball hard at a higher rate than all but ten other hitters in baseball. So if he starts getting it in the air more often like he usually does, it could pay big dividends.

With the early returns in, it looks like Carpenter is trying to be more aggressive in the zone, a continuation of what he began doing in 2015. He's also  making more contact than he did last year, which is probably a breathe of relief to those who have grown concerned about his K rates. Pitchers have slightly changed their approach to Carpenter as well, by giving him less to hit. However, it's not all improvements, as he's been less effective thus far at getting the ball in the air, and while the Home Run per Fly Ball rate is still above 2013 and 2014, it's so far below 2015. That gets us back to an obligatory statement on sample sizes though, especially considering that if not for Billy Hamilton, the rate would be almost a match for last year's HR/FB%.

None of this is set in stone, but again it gives us something to watch for as the season progresses, and a few months from now we'll have much better ideas. As he is probably the best hitter on the Cardinals going forward, it will be interesting to see how this cerebral hitter continues to evolve in 2016.