Steven Kwan still isn’t getting a fair strike zone

As we wait for numbers to stabilize as sample size grows, most of us are futilely looking for anything in the data that might be something. In my piece last week, I looked at some way too early things that might be trends and included the fact that Steven Kwan had big differences in his 2022 versus 2023 swing rate, swinging strike rate, and walk-per-strikeout rate. This was only through 25 PA, so it was officially nothing, but worth watching.

With more than twice as many plate appearances (55), his stats are coming down toward “normal” — if you can call a sample size of one season normal. All those rates mentioned previously are now closer to last season (2022 numbers in parentheses), with his swing rate now 40.3% (37.7%), swinging strike rate 4.6% (3.1%), and walk-per-strikeout rate 1.00 (1.03). These numbers have fairly large swings daily at this point in the season, on the order of a full percentage point in some cases, so it must be taken with a grain of salt.

However, another trend that is slightly more static has emerged, and it might explain Kwan’s plate discipline numbers through the first nine games of the season: Umpires keep expanding his strike zone.

From Kwan’s 233 total pitches seen, we can isolate 48 called strikes, or 20.6% of all pitches he’s faced, the most on the team. As the leadoff hitter, it’s obvious that Kwan will have the most plate appearances and, thus, it is logical then he would see the most pitches of anyone on the team. That he might also have more called strikes is not a huge leap either, but the location of the strikes is making a difference.

Using Baseball Savant’s zone, we can see that, of Kwan’s called strikes, five have been fully outside the strike zone (2.14%). This trend is not simply a 2023 thing, either, as Kwan led the team last year with 76 of 2,643 called strikes being fully outside the strike zone. He led the team in both categories, with 24.5% of his pitches being called strikes and 2.9% of those being fully outside the zone.

Several unanswerable questions arise from this trend. Is this a Kwan thing? He came to the big leagues with a reputation for being a selective hitter, which perhaps was internalized by umpires. Is it a leadoff hitter thing? Christian Yelich is the current league leader in called strikes fully outside the strike zone (12), and he’s batted leadoff for the Brewers in seven of their 10 games.

Or maybe it’s a star thing? Kwan’s loud entrance last year immediately put him in the upper echelon of Guardians’ batters, right there with José Ramírez. Among Guardians batters in 2023, only Ramírez has more called strikes fully outside the strike zone (6); last year Ramírez was second to Kwan, with 54 (2.0%) to Kwan’s 76. Along that line, is it possible that umpires, with their fallible human nature, are expanding their strike zone against Kwan because they expect him to get hits? Maybe Kwan is being subconsciously included among the elite at making contact, like Ramírez, whose swinging strike rate since his debut in 2013 (5.4%) is the fifth-lowest among all qualified hitters.

There aren’t answers to these questions, but there are results — to a small degree, at least — from these umpiring decisions. Namely, Kwan is having more pitches called strikes and, possibly, having to be less selective about the pitches at which he’s willing to swing.

With the sample that we have so far, this is a thing that has happened. We’ll have to wait and see if it’s really anything.