Why are the Royals striking out more this year?

One of the biggest reasons, perhaps the biggest reason, why the offense has struggled this year is the strikeout. After being the best, historically so, at not striking out last year by a large margin, the Royals have managed only the 10th-best strikeout rate - from 15.9 percent to 20.1 percent. Obviously, a team that relies on putting the ball in play is going to be worse at scoring runs when they’re putting the ball in play less.

Royals fans are generally aware of the above, though it will differ from fan to fan on how specific their knowledge is. What I’m setting out to do is trying to figure out why. This almost certainly won’t be solved in one article, so maybe there will be multiple.

One level deeper from the strikeout rate would be the plate discipline data. I don’t think it’s totally necessary to show you that exact data. Click here. Also click here for the PITCHf/x version. Both sets of data tell the same story - the Royals have swung more, both inside the zone and outside the zone, and have missed more, both inside the zone and outside the zone. The first-level peripherals suggest the strikeout rate is not a product of random variation.

If the Royals have altered their swing tendencies, which the plate discipline data suggest, the first place I thought to look was pitch location to see if there were any differences between this year and last year. What follows is a series of heatmaps comparing 2015 vs. 2016 for right-handed hitters and left-handed hitters. Data from Baseball Savant.

2015 RHH pitch location

2016 RHH pitch location

Well, there’s quite a clear difference in pitch location to right-handers. Last year, pitchers tended to stay away. This year, they have come more inside. I would also say that the pitch location in general is lower, but the boxes framing our perception of the heat map appear to be different sizes. The 2016 box seems to elongate more on the high side...does that mean more high pitches have been called for strikes? I’m not really sure.

2015 LHH pitch location

2016 LHH pitch location

The general location is roughly the same - away. However, it also looks like there’s a bit more inside pitches and a bit more low pitches. Again, there’s that strange elongation at the top of the box framing our perception, but this time it’s in 2015. I don’t know.

So maybe there have been a few changes in pitch location, the most noticeable being more inside pitches to RHH and some more low-middle pitches to lefties. So are there any changes in swing location?

2015 RHH swing location

2016 RHH swing location

MAYBE THEY SHOULD LAY OFF THE LOW AND OUTSIDE PITCH.

Ahem. As pitch location has shifted more inside, Royals righties have swung more there. However, there still is a chunk of pitches heading to the outside corner, and the Royals are swinging there less. Maybe that’s a spot where more called strikes are happening? Something to investigate later.

At any rate, there’s nothing really surprising about the shift in swing location. It just follows the shift in pitch location.

2015 LHH swing location

2016 LHH swing location

The distribution is kind of all over the place, but you can see a concentrated dot in the low-middle area, where there has been an increase in pitch location. That makes sense.

Overall, it roughly looks like the Royals’ swing distribution changes have followed the pitch distribution changes. Nothing surprising. So where are the Royals whiffing more?

2015 RHH whiff location

2016 RHH whiff location

MAYBE THEY SHOULD LAY OFF THE LOW AND OUTSIDE PITCH.

Ahem. Right-handers are whiffing in the same location in each year, except 2016 sees the addition of what is most likely the high fastball.

2015 LHH whiff location

2016 LHH whiff location

As pitch location has shifted more toward low and inside, lefties have whiffed more low and inside. The area also appears to be larger. Up and away is still there.

Tying everything together, the Royals’ swing distribution has simply responded to how pitchers have decided to attack the hitters. There is nothing glaring about at which pitches the Royals are swinging that sets off any alarms. As far as whiffs go, righties are missing more high pitches, and lefties appear to be missing a wider swath of pitches.

The next part of this will look to incorporate pitch types.