So How Good Has J.D. Martinez Become?
People love a breakout, so they’re always on the hunt. You’ll see a bunch of potential breakouts get written up in the first half, as season sample sizes start to grow. Among those potential breakouts, you will find the actual breakouts. But you’ll also find the noisy duds, because it turns out half of a season has a limit on how meaningful it can be. In the first half of this season, Lonnie Chisenhall posted a 163 wRC+. In the second half of this season, he’s posted just about the same wRC+, except without the 1 in it. Chisenhall’s gotten much much worse. Early on, J.D. Martinez was another potential breakout. As I write this his wRC+ is sandwiched between Giancarlo Stanton‘s and Paul Goldschmidt’s. Martinez, to a large extent, has kept things up, and he’s produced like one of the top hitters in baseball.
Because one half of one season can be noisy, two halves of one season can be noisy, particularly when a guy hasn’t been a full-time player from the start. Martinez hasn’t totally established his new baseline yet, but it’s not like this came without warning — Dan Farnsworth was all over it in December. I think we can see J.D. Martinez is better. So the question is: How much better is he?