The Royals have had a plate discipline problem for awhile

Earlier this week over at the Ringer, Ben Lindbergh wrote a fantastic article about the unprecedented improvement of Lorenzo Cain’s plate discipline. Much of the piece revolved around his large decrease in chase rate this year.

Cain’s chase rate last season was 31.7 percent, a full percentage point worse than the league average for non-pitchers. As of today, his chase-rate decrease relative to last season would be close to the largest in the pitch-tracking era (2008-18). The table below lists all year-to-year decreases of at least eight percentage points among hitters with a minimum of 300 plate appearances in both years.

After reading this, I didn’t initially think of the role the Royals might have had in this. But then after some scrolling on Twitter, I came across this tweet by Rany Jazayerli.

Rany brought me the idea of the Royals possibly being involved with this, in a sense that they implement a different type of hitting philosophy into their players. A hitting philosophy that encourages more swings, more chasing, and less patience. This shouldn’t come as a surprise to most fans too, as their success in 2014 and 2015 related to not striking out, putting the ball in play, and relying on some BABIP. Basically as a team, they were the opposite of a true three-outcome team (and they still are today, even in their fall). Since 2014, they’ve struck out at a lesser-rate than every other team, while walking at a lower-rate than every other team.

Holy outlier.

Looking at the numbers, it is easy to come to a conclusion that the Royals push an aggressive approach. Going to back to the beginning of 2014 again, the Royals lead baseball in percentage of swings out of the zone, frequently chasing pitches that are harder to hit. They also swing the bat more than any other team in that time.

The Royals offense is bad now mostly because of the departures of Lorenzo Cain, Eric Hosmer, etc. However, it also wouldn’t be a stretch to say their lack of ability to adapt to the ever changing field of baseball has hurt them, particularly in 2016 and 2017, when the trend of being a “true three-outcome” player started to take off.

I guess you could say teams like the 2014 and 2015 Royals were better served playing in their respective seasons. With the exponential soar of home runs, the rise of the shift, and BABIP levels being at one of the lowest marks in recent history, the brand of offense the Royals played back then would be harder to implement successfully now.

FanGraphs

I felt the best way to get a grip of what the Royals are pushing for at the plate was to look at it through the eyes of incoming free agents, trade acquisitions, and waiver pickups. The idea was to look at the changes this group of players made once getting in the hands of Royals personal, wanting to look at the changes they made by switching from organization to organization.

To start, I found season-to-season correlations in three stats I feel best represent the level of aggression in an approach, those being out-of-zone swing percentage (O-Swing%), swing percentage, and walk percentage (BB%). Using three seasons as my data range, I found that typically these stats have little variation year to year for a hitter.

• O-Swing%: r=0.87
• Swing%: r=0.87
• BB%: r=0.79

Using these three correlation coefficients as a benchmark scale, I found the season-to-season correlations for players that are either traded, signed, or picked up by the Royals (example would be comparing Ben Zobrist’s numbers with the Athletics to his numbers with the Royals). Here’s what I found.

• O-Swing%: r=0.74
• Swing%: r=0.65
• BB%: r=0.72

While there’s still a bunch of correlation in that group, there seems to significantly more variation from Royals acquisitions. Averaging it out as a group, these Royals acquisitions see an increase in O-Swing%, Swing%, and most notably a decrease in BB%. Averaging out the season before every Royals acquisition, we come up with a 9.2 percent BB%. Averaging out the same group’s first season with the Royals, we come up with a 7.9 percent BB%. Perhaps a perfect example of this would be Lucas Duda this year, as he is currently posting career highs in O-Swing% and Swing%, while posting a career low in BB%.

The Royals had a style of play that ran them to success in 2014 and 2015. But in the ever-changing game of baseball, teams have to adapt. The Royals have done the opposite of this, as the team still ranks near the top of baseball in swings and swings outside the strikezone, while walking less than any other team. This may seem harsh, but the game has changed and if baseball keeps progressing in its current trends, the Royals will probably have to change with it. If not, when contention is a possibility again in years down the road, their current organizational philosophy will have trouble finding success once again.