Matt Carpenter might have a problem

Not many people ever expected much of Matt Carpenter at the MLB level. He was a late-round draft pick (taken in the 13th round of the 2009 draft), and because he was taken as a college senior with no leverage if he wanted to play professionally, it only took a $1,000 signing bonus for the Cardinals to bring him into their organization. His minor-league lines were pretty good, but scouts never really bought him as more than a role player (if that) at the MLB level. Though he had a good rookie season as a part-time player in 2012 — 124 wRC+ in 340 PAs — few can honestly say they saw that year as a sign of stardom to come.

Then in 2013, his first full year, he finished 4th in NL MVP voting, on the back of a 7 WAR season. As it turned out, Matt Carpenter had a particular set of skills, and those skills made him a really good hitter.

Foremost among those skills is the one everybody knows about: plate discipline. It’s Carpenter’s defining trait as a player. He doesn’t swing at balls. He doesn’t swing much at all, really — he routinely has one of the lowest overall swing rates in the league — but he especially doesn’t swing at balls. Because he doesn’t swing much period, and especially not at balls, Carpenter has always walked a lot. Which is great, and which is something you already know.

Carpenter’s other great skill, though, has been (at least for me personally) easier to miss. It doesn’t show up in a triple-slash line the way walks do. In addition to being one of the most patient hitters in the league, Carpenter has very good at making contact. He hasn’t been elite at it — not the way he has been at taking non-strikes — but he’s been very good: from his first full season to the present, Carpenter is 65th out of 324 qualified hitters in contact rate when swinging. Contact rate alone doesn’t a good hitter make (many of the top guys are slapsters like Ben Revere and Alberto Callaspo) but Carpenter’s contact is by and large good contact, as evidence by his .182 career ISO.

(1) Taking tons of pitches + (2) not missing the ones you swing at + (3) hitting it hard when you hit it = good hitter. This is a straightforward system, and it’s where Carpenter’s career 130 wRC+ comes from.

It’s been a system in some flux in recent years, though. Here’s a chart of (2) in the formula above — Carpenter’s annual contact rate:

You can see the league-wide rate declining, there, but you can also see Carpenter’s rate going from well above average in his first two full years (2013-14) to only a bit above average the next three years. That change didn’t happen in isolation, though. Let’s add another stat — isolated power:

Interesting contrast, right? As Carpenter’s rate of contact decreased, his quality of contact increased. Of course, nowadays there’s no mystery to this. Lots of hitters do this now. He started swinging for the fences — or more precisely, he started hitting the ball in the air more. The tradeoff for Carpenter seems to have been less contact; some hitters (hello Jose Martinez) have been able to avoid that tradeoff, but not Carpenter. Hitters are all individuals.

2018, though, has seen a troubling acceleration in the reduction of Carpenter’s contact rate. Entering Friday night, Carpenter had 70% contact rate over his last 30 games, and a 70.7% rate for the 2018 season. That’s an unprecedented low for him over a 30-game stretch:

It’s tempting to take the big drop in 2015 as an example of Carpenter falling into a funk he later worked out of. But that dip actually coincided with Carpenter starting to hit the ball over the fence more, possibly side effect of a new, air-oriented approach. This year — while it’s certainly true that Carpenter has hit into a great deal of bad luck — the power hasn’t yet manifested to make up for that lack of contact. It certainly could get there (Carp’s expected wOBA based on launch angle and exit velocity compared to his actual wOBA has him as the unluckiest hitter in baseball in 2018), but it’s uncomfortable seeing a guy whose career has been largely based on bat control suddenly look below-average at putting the bat on the ball.

Digging deeper, we can see what really has me worried — Carpenter whiffing at strikes:

He’s whiffed on more balls than usual this year, but Carpenter’s O-Contact% (contact when swinging at balls) is at least in a place where it’s been before. His Z-Contact% (contact when swinging at strikes) is at a historical low, though. Before this year, Carpenter had never had a 15-game stretch under 78% contact when swinging at strikes. This year, at one point his 15-game contact rate on strikes was just 69%. Not nice. For the year, it currently sits at 81.3% — tied for 30th worst in MLB.

The culprit has been offspeed pitches — breaking balls, in particular. Per Brooks Baseball, Carpenter had seen 92 breaking pitches entering play last night. He’d whiffed on 56% of the ones he swung at, a proportion Brooks terms “disastrously high.” Look at this and try to disagree with that description:

Yikes, eh? Granted, the Cards have run into some tough breaking-ball pitchers in the early going (that Robbie Ray and Patrick Corbin pair of games can’t have helped), and it’s only a month. Maybe this is a blip. As in so many things this early in the year, it’s too soon to tell. But let’s entertain the downside scenario, if only momentarily:

Matt Carpenter was a college senior when he was drafted, and spent three years in the minors. He was already 27 when he played his first year as a full-time starter. Now he’s 32. He’s had a range of nagging physical problems over the last few years, mainly in the upper body — shoulder, oblique, back, etc. I don’t know if you’ve ever turned 32, but I have, and I can tell you: you start to notice.

There’s a real chance Carpenter’s fine, or at least basically fine. Maybe he was just in a temporary funk and whiffed on a lot of breaking balls for a month, whether due to a short-term physical issue or a weird confluence of great breaking pitches or pure randomness or who knows what. That could certainly be (and I hope it is) the case here.

Or, maybe he’s getting old. Maybe he’s crossed that invisible line where to stay on fastballs, he has to cheat enough that all of a sudden he’s missing the breakers instead of fouling them off. Maybe this is his new normal. It doesn’t mean he’s a bad hitter now — even with all the new whiffs, he’s been hitting the ball hard enough that with neutral luck he would still have been a productive hitter so far this year. But if this is Carpenter’s new normal, then one leg of his three-legged stool (discipline, contact, and power on contact) might be eroded for good. If the whiffs are here to stay, something else will have to change to make up for them.