BotB Shorts: Matt Carpenter's struggles vs. lefties in 2017



Matt Carpenter is a very good baseball player. In spite of a few contrarians eager to argue otherwise, it's not all that debatable. Since his breakout season in 2013, he has the third most plate appearances in the National League and he ranks in or near the top ten in a lot of offensive categories (runs, hits, OPS) befitting a very good player. And since 2012, he has the highest on-base percentage for any leadoff hitter (.391) in all of baseball (min: 1,000 PAs). In short, he's been dependable each season and he gets on base a lot. I'll take it.


One reason that Carpenter has been a tough out is that he hits righties very well and has always been a well above-average hitter even when he doesn't have the platoon advantage (112 wRC+ in 1,068 career PAs vs. lefties). Until last season, that is. This first came to my attention in the 2018 Baseball Prospectus Annual, which I highlighted last week. In case you missed it, here's the pertinent screenshot from that post:

So first thing's first, Carpenter had only 137 plate appearances versus left-handed pitchers in 2017. That's a small enough sample where a couple of hits here and there and his slash-line no longer looks curious. Let that be reflected in the record.


Even so, let's look a little deeper. Using FanGraphs' Splits Leaderboards, the first thing that jumps out is that Carpenter had a .256 batting average on balls in play versus lefties in 2017, which is about a 50 point drop from his career average. Now maybe that's a result from a different approach at the plate in 2017, or that lefties have somehow solved Carpenter and that .256 number will be reflective going forward. After all, results from 2017 seem more relevant than those from 2013 when we're thinking about 2018, right?


However, if you look at Carpenter's batted ball profile, he had 37.5 percent hard contact against lefties in 2017, which was actually a career high. He was squaring up lefties just fine, but the hits too often found a glove. That happens. And there's nothing else all that notable in the splits that jumps out. Carpenter did strikeout a lot against lefties last year - 23.4% - but that's an actual decrease from 2015, and not an offensive diversion from his career marks.


So I'm chalking this up to rotten luck.


A couple of caveats: The analysis above is very cursory. And such an analysis is not my area of strength. I'm sure some of the Statcast gurus could put together a more interesting perspective, one which I would look forward to reading. Until then, remember that had just five more of Carpenter's at-bats against lefties in 2017 resulted in a hit instead of an out, his average would have increased almost 50 points. All is probably fine, and Carpenter is still a very good baseball player.