The J.D. Martinez story is familiar now. An unorthodox swing led to failure in his major league career in Houston. He completely rebuilt his mechanics following the 2013 season, but the Astros didn't even give him a chance to show them that he was a changed batsman. The Detroit Tigers did, and they were rewarded. You can only ask yourself where they'd have been last season without him. But there's another nagging question: Can he do that again or was he just benefiting from a lucky season?
The likely answer is that he can do much of it again. How much? That remains to be seen. Two key stats to look at when talking about J.D. Martinez are his batting average on balls in play and his home-run-per-fly-ball ratio. Both surged in 2014. The problem is that the changed swing makes it difficult to say how much of his improved numbers came from luck (or year-to-year variation), and how much came from the changes he made as a batter.
Early in his minor league career, Martinez frequently had a high batting average on balls in play: .448 in rookie ball, .398 in High-A, and .372 in Double-A. Line-drive data isn't available, but it's easy to imagine him as a player who rocketed the ball. In the majors, the figure steadily decreased, from .325 his rookie season, to .290 the following year, to .319 in his last season in Houston. Martinez struggled with squaring up on the ball that .290 year, and it's reflected in a career-low line-drive rate of 16.6 percent.
As he has frequently told the story, he noticed the better batters on his team and in the game managed to keep the bat in the hitting zone for a much longer period of time than he was capable of. So he rebuilt his swing in order to give himself a better chance to square up well on the ball. He does that now. With the Tigers, the line-drive rate rebounded to just shy of 23 percent, and the BABIP rose all the way to .389.
The sign of a player whose bat is staying in the hitting zone longer? Probably. Sustainable? Almost certainly not. The highest BABIP among qualified hitters last year was .373 from Starling Marte. Next on the list came the .360 from Martinez's former teammate, Jose Altuve. These players have wheels that help them beat out throws. Martinez does not come so equipped. Expect him to fall back to earth in the batting average category, and his on-base percentage will follow along. It should, however, fall in the upper-200s rather than the mid-to-lower.
Then we have the power thing. Without a doubt, Martinez is blessed with power. Watching him in batting practice is a pleasure. Then you watch him in a game and he deposits baseballs over the wall dead center in Comerica Park. Manager Brad Ausmus described Martinez as having "elite" power that you just don't see in the game. Martinez had career-best success in the HR:FB ration last season at 19.5 percent of fly balls leaving the park. He hadn't eclipsed 11.5 percent before.
If you want to put Martinez's HR:FB success in perspective, Miguel Cabrera's is 19 percent for his career, and in only four of his 12 seasons has he posted higher figures than Martinez did last year. Only five qualified batters -- led by Jose Abreu of the White Sox, and a list including Giancarlo Stanton, Chris Davis, Nelson Cruz and Matt Kemp -- hit with a higher HR:FB rate than Martinez. New swing or not, it seems like it's asking a lot of him to keep hitting at that level of power.
The other interesting aspect of Martinez's game to keep a watch on this year comes in the field. He has spent most of his time in the majors in left field. With Yoenis Cespdes owning that position this year in Detroit, Martinez is headed to right field. He's only logged 437 innings there in the majors, but he appears to make for a better right fielder than left. That could help the overall value of his contributions to the Tigers rise. In any case, it's a darn sight better than watching Torii Hunter out there.
Stats and projections
Martinez signed a one-year, $3 million deal for 2015 to avoid arbitration, his first year eligible. He has two years of arbitration remaining and becomes a free agent after 2017.
Martinez has hit well this spring, with a .347 average and .735 slugging. The power is still there. Anyone expecting him to fall off a cliff like some sort of one-year wonder would be mistaken. He's going to continue to be an important batter in the middle of the Tigers' order in 2015. Just don't expect him to repeat the figures he put up in 2014.