Matt Carpenter and power efficiency



On Sunday afternoon in the final game of a five game series with the Chicago Cubs, Matt Carpenter failed to hit a home run. Normally, a homer-less game wouldn’t be notable, but this one was the first time since July 13th that Carpenter failed to hit a home run in a game. He left the yard six games in a row. He blasted eight dingers in six games. If not for this catch by Billy Hamilton, he would’ve had a homer in seven games straight.


Back on May 16th, Carpenter owned a dismal 68 wRC+. Since May 16th, it’s at 210. There are 250 other players who took at least 75 plate appearances before and after May 16th. Matt Carpenter’s 142 point improvement is the largest.



Carpenter is really good hitter, but no one saw that coming.


Near the end of June, Jay Jaffe of Fangraphs paid due to the St. Louis Cardinals third/first/second baseman’s turnaround since his rock bottom on May 16th. Today, almost a month later, Matt Carpenter ranks as the best hitter in the National League and has the slight edge in a virtual tie for the highest WAR among NL position players.


I don’t pay much attention to prospects and I paid no attention to them eight years ago. I don’t know what evaluators thought about Carpenter’s future in the MLB, although I didn’t see him on MLB.com prospect lists and he showed up as only #12 in John Sickels’ 2012 list. Despite his lackluster prospect shine, he’s become the Cardinals fourth most valuable positon player this century. Matt Carpenter wasn’t supposed to be this good, but he’s excelled by maximizing his skillset.


Over the past few weeks, I’ve been working with Daniel Beattie (@216stitches) of 216stitches.org to develop a few different metrics using Statcast data via Baseball Savant and which are intended to resemble the traditional scouting metrics (our metrics include data up until the All-Star game, so they aren’t capturing Carpenter’s recent tear). One of those metrics is Game Power, which measures how often a player hits batted balls that are likely to be home runs or at least extra bases. It’s similar to barrels per plate appearance as shown on Statcast, but doesn’t require us to know how often batted balls are hit, or what the slugging percentage on similar balls is, or what the wOBA on similar batted balls is. Our Game Power measures how often a player hits the ball at least 95 mph and at a launch angle between 22 degrees and 38 degrees. How hard and how high?


Here are the annual leaderboards (min 300 PA in 2015-17, min 200 PA in 2018). I apologize in advance for the inclusion of gridlines and the exclusion of year labels, but my Excel has crashed too many times today to count and I didn't want to remake the leaderboards again. 2015 is on the far left, 2018 is on the far right, 2016 and '17 are in between (obviously).


*Read left to right from 2015 to 2018

Carpenter ranked 10th in 2015, the first year he began trying to hit for more power. He ranked second in 2016 and again in 2018. He only missed the top ten cutoff in 2017, when he ranked 21st. The only other player who ranked in the top ten three times in four years is JD Martinez.


Martinez fits the bill of players who come to mind when we think power. He’s ranked in the top 30 by average exit velocity and top 10 by barrel rate every year since 2015. Aaron Judge, Giancarlo Stanton, and Joey Gallo are similar. Power hitters are supposed to mash the ball. Matt Carpenter doesn’t, but he gets powerful results due to how often he drives the ball at a productive angle. You might say he has “efficient power;” that is, he gets more out of the power he has than those prototypical power hitters.


To measure “efficient power,” I compared each players Game Power with their Raw Power (how good a player is at generating the hardest batted balls) and standardized each metric assuming a normal distribution. Players with efficient power will rate better, relatively, by Game Power than they do by Raw Power. Here’s our leaderboard since 2015:



This list passes the eye test. Most of the players are below average at generating batted balls at the highest exit velocities but above average at hitting for power, whether its home runs or just extra bases. The majority of them are considered excellent power hitters. Matt Carpenter ranks just behind Josh Harrison for having the third most efficient power in the Statcast era. Focusing in on just 2018, he ranks second behind only Alex Bregman. Again, this doesn’t include his streak since coming back from the break. If it did, he’d certainly rank even better.


I think, really, this encapsulates Matt Carpenter. His average home run distance this year is 390 feet, which ranks in the bottom 25 among players who have hit at least ten, as does his average exit velocity of 101.9 mph on those homers . He hasn’t hit a single dinger this year with an exit velocity of at least 110 mph (his hardest was 108.2 on June 19th). Despite the lack of obvious power, though, he’s tied for the NL lead with 25 home runs and with 30 doubles.


The St. Louis Cardinals season has been lackluster, to put it lightly. They probably aren’t making the playoffs and it’s difficult to imagine them making a big splash at the deadline as buyers or even as sellers. There are still bright spots and reasons to pay attention, however, even with the team caught in "pre-tention." Matt Carpenter wasn't an all-star, many Cardinals fans think he's a problem, and he likely won't be a legitimate MVP threat at the end of the year. But he's making the most of himself and forcing us to pay attention.