How an expanded strike zone is affecting Rays hitters

If you watched recent MLB games or the Rays games closely, You will notice that the strike zone seems to have expanded. Here are some examples:

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As a result of widened zone, hitters are, well, not hitting. The MLB average slash line has fallen to 234/.310/.392/.702. If you are a .240 hitter, it means you are now better than league average. If you’re .220 hitter, don’t worry about it. You are in good company.

If you have been wondering why offense is down this year, look no farther than those Texas-sized strike zones. I’m not going to talk about why this phenomenon is happening; rather I’m going to talk about its impact.

My hypothesis is that batters who lack contact ability, especially for pitches outside the zone, will have more difficulty because of this change. So I picked 25 batters with the lowest O-Contract% across 2019 to 2021 and compared their 2019-2020 OPS+ (I prefer the wRC+ but it doesn’t make a big difference) to their performance as of May 2, 2021:

(Source : Fangrahps.com, Baseball-reference )

A statistical conclusion cannot be reached a sample of this size. But we see some immediate effects. I found that many batters on this list are starting the season with poor performances. The same is true of Brandon Lowe and Willy Adames, who have had slow starts to their seasons. Perhaps they have been having trouble covering the widened zone. Perhaps you can easily sense their confusion as we watch Lowe and Adames at bat.

On the other hand, there are batters who are less affected by this change or seem to be adapting quickly. While league average O-Contact is around 60%, Rays hitters like Yandy Diaz (78%), Joey Wendle (69%), and Manuel Margot (67%) are over achieving and accordingly having better starts to the season.

Pleaser like Wendle and Margot have no big holes in their swings and are capable of covering all spots, including outside the zone. They swing more aggressively and don’t seem to be affected by the changed zone by much.

To pick two examples to illustrate the difference in approach, compare the performance of some players we’ve highlighted thus far in AVG by pitch location:

(Source : Fangrahps.com )

Compare Wendle, Margot, Lowe and Adames’ hot-zone in a small sample size thus far.

Lowe and Adames’ Hot-zones are more central, and they rarely make a hit on the borderline pitches or pitches outside the zone. In the past, Lowe and Adames’ weaknesses may not have been a big problem because borderline pitches were often called as balls. But, in this season, these balls that they don’t want to hit or can’t hit are being called as strikes, which is probably confusing to them. (And, also, we should keep in mind that they’re fly ball batters trying to get some power on that unjuiced ball).

So how long will this phenomenon last? We really don’t know whether the wider strike zone is going to stick around.

Good hitters are adjusting all the time, and hopefully Lowe and Adames will be able to adapt to this new reality.