Remember way back in 2014 when J.D. Martinez overhauled his swing and became one of the best hitters in baseball? Of course you do. You’re reading a Tigers website. He came up with a lot of raw power but couldn’t get his skills to translate on the field and wound up getting cut by the Astros in the spring of 2014. He had been working to change his swing and the Tigers gave him a shot. He raked in Toledo, got called up to Detroit, and went on a tear for the last division-winning team of the Dombrowski era.

We all liked Martinez, but most of us were also concerned about the other shoe. After all, these late career breakouts are rare and all we had was a .389 BABIP over 480 PA. In other words, we held our breath for 2015, hoping that our favorite team had actually struck gold rather than stumbling into pyrite. Last year, Martinez reassured us all with another terrific season. He delivered a 137 wRC+ and 5.0 fWAR. Martinez was for real.

And then came the first month of 2016. Martinez had just eight extra base hits in his first 128 plate appearances and was running a 78 wRC+ for the season. We were past the point of calling him a fluke for his previous two seasons, but given the struggles of some other Tigers, the concern that the league was finally figuring out Martinez did start to creep up.

But then!

Over the last 57 games, J.D. Martinez has been the best he’s ever been, in terms of wRC+:

One big difference during his hot streak compared to before is that he’s swinging the bat a lot more often (roughly 55% compared to 48%). You can see that his recent swing rate is more in line with his successful period.

Granted, I was certainly one of the people who was concerned about his swing rate when he first got going back into 2014. Typically, hitters who strike out like he does without taking their walks are limited even when they have significant power. Martinez has been able to increase his walk rate during the last two years and maintain it even now that he’s swinging more.

Every hitter has their own equilibrium. If Martinez hits better when he’s being more aggressive, he should continue to be aggressive. You don’t take pitches just to take pitches, you take pitches that you can’t do damage against. Right now, he’s making good choices and delivering results.

Now, if your eyes are drawn to the WAR column at Baseball-Reference or FanGraphs, you’ll notice he’s not quite keeping pace with his previous levels because both defensive ratings think he’s been much worse this year. From watching, I would tend to agree that he looks much worse this year compared to 2015, although we could probably quibble about the exact magnitude.

With Justin Upton, Miguel Cabrera, Victor Martinez, and J.D. all hitting, the Tigers lineup becomes as frightening as any in baseball. I don’t think anyone was on the ledge about J.D. after the first month of the season, but the Tigers were counting on him to be a premier hitter coming into the season and their margin for error was quite small in the playoff race. He got off to a slow start, but he’s made up for lost time, even if he hasn’t yet made up for the actual time he lost with a broken elbow. Perhaps the last five games are Justin Upton’s signal that he’s ready to do the same.