A dissection of Matt Carpenter's batting deflation

Playing second base, Matt Carpenter had a breakout 2013 campaign that was perhaps even better Robinson Cano's offensive output when the differences in batting at Yankee Stadium and Busch Stadium are considered. Carpenter posted the following hitting line:

Carpenter led the NL in hits, runs scored, and doubles. Not surprisingly, given his outstanding production, the Redbirds' second-sacker placed fourth in the NL MVP vote.

This spring, Matt Carpenter and the St. Louis Cardinals agreed to a contract extension worth a guaranteed $52 million over at least six years. The extension was typical for its kind, buying out Carpenter's cost-controlled years and some free-agency seasons. The deal gave Carpenter financial security and the Cardinals cost certainty at a price that would be very team friendly (if he maintained his elite batting) or fairly team friendly (if he wound up never again reaching the heights of offensive production to which he soared in 2013).

Over the first 221 plate appearances of Carpenter's six-year contract (which will see thousands more PAs during its term), the St. Louis third baseman has not hit like he did last season. While it was fairly predictable that Carpenter would not bat at 2013's MVP-caliber level, the way in which his numbers have deflated offers some surprises.

Carpenter's .359 BABIP a year ago was far higher than the MLB non-pitcher BABIP of .299. So the fact that the Texan's BABIP was fallen 23 points so far this year isn't at all shocking—it's expected. And at .336, Carpenter's 2014 BABIP is still well above the MLB non-pitcher BABIP of .299 this season. Carpenter is still elite at having the baseballs his bat strikes land in play safely, just not as other-worldly awesome at it (or lucky, if you prefer) as he was last year.

BABIP accounts for some of the sag in Carpenter's batting average, which currently sits 47 points lower than the level at which it ended 2013. Oddly enough, though, the other driving factor in Carpenter's BA falloff has been strikeouts. Carpenter is striking out in almost five percentage points more of his PAs. That's a startling 32.1% increase in strikeouts.

Carpenter is also suffering from the power sap that has infected the Cardinals lineup (non-Peralta division) as a whole. Last year, Carpenter led the league in doubles and consequently posted a healthy .163 Isolated Power (known as ISO for short, this stat subtracts singles from a player's slugging percentage and consequently reflects only extra-base hits). Carpenter's ISO of 2013 was comfortably above the MLB non-pitcher ISO of .146 in 2013. This year, Carpenter is barely hitting for any power at all. His minuscule .059 ISO is far less than half the MLB non-pitcher ISO of .146. For a bit more context, Aaron Miles posted a career ISO of .072.

In spite of his lower average, Carpenter's OBP still sits at an elite .371 because he has increased his walk rate. This is the driving force in Carpenter still being an above-average batter in 2014 despite an increase in strikeouts, decrease in BABIP, and nonexistent power.