When Detroit Tigers manager Brad Ausmus made a change to his batting order less than a month into the season, the decision seemed obvious. Replacing the No. 2 hitter Justin Upton -- who was hitting just .208 with 39 wRC+ -- with J.D. Martinez and his .278 average and 107 wRC+ seemed like a no-brainer.
Since this swap, both players have further justified the decision as they trend in opposite directions. However, a curious thing has happened to Martinez since moving up in the batting order.
The short of it is simple: Martinez has sacrificed average for power. While his power numbers -- and subsequently his wRC+ -- are much improved since batting second, his average and on-base percentage have declined. Though his walk rate is up from 8.6 percent to 11.0 percent, his strikeout rate has jumped from 18.5 percent to 26.4 percent. It would be inaccurate to call Martinez a bust as the No. 2 hitter because he has been anything but that with his 142 wRC+.
However, the Tigers might be wise to move him back to fifth in the batting order again.
|4/5 - 4/26||81||.278||2||18.5%||107|
|4-27 - current||91||.253||6||26.4||142|
Attacking the top
Pushing Martinez up in the batting order is not what caused the change in his game, but it serves as a clear break-point in his season thus far. The first 19 games of the season were decent for Martinez, but he lacked the same authority that he displayed in recent seasons. For example, in both 2014 and 2015, almost 40 percent of his hits went for extra bases; to start 2016, this number was at just 25 percent. He was hurt as well by his 8.30 percent home run to fly ball ratio (HR/FB), which was not near his 16.2 percent career average.
Suddenly, the numbers began to change. The home runs started coming as the average fell, and fly balls were replaced by grounders. What brought upon this change? One big difference in Martinez’s approach was his decision to swing at higher pitches. To begin the year, he only swung at 46.9 percent of pitches at or above the middle of the strike zone; after moving up in the order, he raised this mark to 60.1 percent. Perhaps unsurprisingly, all eight of his home runs this season have come from pitches in this area.
Looking at Statcast data further emphasizes this difference. During the first part of the season, Martinez’s launch angles were somewhat equally distributed between ground balls (10 degrees or less), line drives (between 10 and 30 degrees), and fly balls (over 30 degrees). However, starting at the end of April and moving into May, Martinez began hitting a much larger portion of balls into the ground while sharply cutting his fly ball rate.
|Launch Angle||4/5 - 4/26||4/27 - current|
|under 10 deg||36%||47%|
|over 30 deg||32%||18%|
Putting these pieces together, it becomes clear that Martinez had a change in approach. He has attacked balls that are higher up and experienced both the rewards and the risks. Hitting pitches higher in the zone will bring about more ground balls, as batters will often swing over them. Though ground balls in general lead to a higher batting average, the types of grounders that Martinez is hitting will not reap such benefits, as many are sharply pounded into the turf- almost 30 percent of his batted balls since late April have a recorded launch angle less than zero.
So what is the benefit of swinging at these pitches? Power. The sweet spot in terms of launch angle lies somewhere between 15 and 35 degrees. During the first few weeks of the season, Martinez averaged a 92.8 mph exit velocity when finding this range; since then, he has averaged 97.7 mph. The result has been a 31.30 home run per fly ball rate with over 55 percent of his hits going for extra bases in recent weeks.
Back to fifth
While batting in second, Martinez has compiled 142 wRC+, which ranks among the top five in MLB No. 2 spots, but his .341 OBP falls in the middle part of these rankings. Though Martinez will likely improve at hitting the higher pitches and will bring up his batting average, right now he is not getting on base enough to maximize the lineup for those hitting behind him. His home runs are certainly valuable, but the Tigers would be best served swapping Martinez in the batting order again.
If Martinez settles back into the No. 5 spot, he should trade places with Nick Castellanos this time instead of Upton. The Tigers’ third baseman has been enjoying an incredible start to the year and has posted a .410 OBP and 204 wRC+ during Martinez’s stint batting second. Until he can get on base a little more frequently, it only makes sense to put him behind Miguel Cabrera and Victor Martinez. While moving down in the order may not seem like a promotion, J.D. is unlikely to mind flexing his re-found power with these two hitting in front of him.