Diving deep into Isiah Kiner-Falefa’s defensive limitations

Look, I’m not here to bash Isiah Kiner-Falefa as a person. He seems like an extremely hard worker with the drive to be a productive major league player, and he doesn’t deserve the over-the-line vitriol directed at his family. What I’m doing here is questioning the Yankees’ analysis of IKF as a highly-skilled defensive shortstop. There have been several instances that make me feel like they’re doing everything they can to confirm their belief that IKF is a great defender because they made the trade for him. In other words, if this isn’t confirmation bias at its finest, then I don’t know what is.

You’ve heard me say this before, but I strongly prefer Statcast’s Outs Above Average (OAA) metric to other publicly available defensive metrics. Why? The main reason is that they have more data. It’s not a perfect metric because there is no such thing as one, but it aligns with the eye test more than any other defensive metric. On the year, IKF ranks in the 29th percentile for OAA, well below average but not the very worst.

This makes a ton of sense! Kiner-Falefa gets decent reactions and is quite a fast mover (82nd percentile sprint speed). He has decent range, but often lacks the footwork to make many plays that are possible from a pure “he got there on time” standpoint. Zooming in a little, Statcast tells us that this is mainly due to his limitations at charging the ball. He has -8 OAA on plays that they define as “In” and last year that same number was -13.

The above leaderboard shows shortstops with at least 100 plate appearances at the position in 2022. Kiner-Falefa, and other Yankees shortstops, play deeper than almost anybody in the league. When considering his weakness in charging the ball, it’s a bit confusing to see that he plays this deep on a consistent basis. The Yankees have their reasoning for this shift, but to me, it feels as if they are exposing their shortstop’s most glaring limitation.

Now, charging the ball is an important trait for a shortstop to have, especially for those who play very deep. The skill is difficult and requires a few abilities. The first is the read off the bat — this is all about instincts. Reading swings and pitch locations aren’t easy things to do from shortstop, but they’re how the best defenders create the right angles and attack the ball with the most efficient footwork possible. The latter two points are the other aspects of charging the baseball: angle and footwork.

So why does Kiner-Falefa consistently struggle with these tasks, and how do the truly elite defensive shortstops do it? There’s plenty to explore here. Starting on Sunday against Tampa Bay, we saw two plays from IKF which are perfectly representative of his struggles. The first was a fielding error on a rolled-over groundball with Frankie Montas on the bump and Manuel Margot at the plate.

By all definitions, this is as routine as routine gets. It’s not the first time that Kiner-Falefa has done this during the season, so it’s not as if I’m nitpicking either. I should make it clear that this is considered a ball that he has to move in for by Statcast’s definition since it required him to move from his original position.

Okay, now let’s think through the feet. To do this, I’ll show you the video in slow motion:

Kiner-Falefa starts off decently enough. To field a routine grounder right at you, you should start to create an angle around the ball, which drives your feet towards first base. This gives your hips and hands space to work through to first base on a more direct angle, rather than fielding the ball and then adjusting your body to make the throw.

However, from that point on, Kiner-Falefa has a change of thought because he misreads the hop. This may be due to him not being used to the faster groundballs on turf, but let’s be honest, that’s not an excuse for a major league shortstop to make an error on a grounder this easy.

The hesitation is enough to keep Kiner-Falefa flat-footed on a crucial step in which he should be aligning himself to first base. It shifts his weight backwards, leading to him trying to create the angle with a drop step in his left leg. It’s quite possible that he could have made the throw from this position, but he needed to overcome it with a rapid-fire exchange and side-arm throw. He failed to do either.

Watch Francisco Lindor instead:

I know that I’m picking arguably the best defensive shortstop here, but there’s reason for it. Lindor makes routine groundballs look routine. There is a moment here when he stops his weight shift. Why? Because he is reading the hop so he can readjust his feet to make that angle towards first base that we’ve talked about. In that pause, he maintains his athletic position, making the weight shit/feet realignment smooth and easy.

Meanwhile, when Kiner-Falefa has his pause to read the hop, he loses his legs from under him. It’s so simple, but this movement is the difference between making the play and not making the play. Just like hitting, it’s very important to stay connected to the ground and keep your legs under you.

A few innings later, Kiner-Falefa had a chance to redeem himself. He changed his tempo attacking the ball because he knows that whatever he did last time did not work. Jose Siri is very fast — 99th percentile fast, in fact — so the shortstop rightfully had a little fire under him on the grounder.

However, the ball was hit decently hard and Kiner-Falefa was probably in too much of a hurry to get Siri. Just like in the previous misplay, IKF does not stay connected to the ground and does not create a direct line towards shortstop with his hips. Instead, he attempts to throw off one foot with all the time in the world to make the play. It’s frankly baffling to see. I don’t want to argue that it’s a mental thing, since he’s made similar plays many times this year, but I’m dumbfounded at the decision-making process.

Even on another play which is a routine flip, Kiner-Falefa finds himself off-balance. The proper sequencing here is staying in an athletic position while taking a slight side-shuffle while opening up his hips to second base with two feet underneath him. Again, he takes a one-legged staggered approach to the ball and looks clearly uncomfortable doing it. The play is made, but it’s another example of IKF not having the proper fundamentals to make routine plays with 100-percent confidence.

Again, back to Lindor:

Chop, chop, chop, enter the fielding position and follow the flip through the bag. This is another tactic to handle this type of groundball.

I’m not saying that Kiner-Falefa needs to be Lindor! Rather, he could learn a lesson or two about how to change tempos and create angles to make plays easily. I didn’t select plays of Lindor running into the hole or up the middle and doing something that nobody else can. These are tailor-made plays that should be replicated by any MLB-caliber shortstop.

I’ll leave you with this: Great shortstops know how to change their stride length on the drop of a hat to readjust their body and make a play like this one from teammate Oswald Peraza:

The rookie was preparing to flip the ball, and then suddenly realized that he could make the play on his own if he took a few shorter strides and oriented himself toward second. Honestly, this is something I’ve never seen Kiner-Falefa do. I’m sure he has made a play similar to this one, but it’s never this smooth or with this awareness of his body.

Proprioception affects every aspect of baseball. Knowing where you are on the field and how your body moves on the field all affect outcomes. Isiah Kiner-Falefa’s fundamental limitations at shortstop are negatively impacted by his ability to readjust his body while making plays. These are things you can get away with at second and/or third (where he’s actually won a Gold Glove), but at shortstop, the holes are exposed.

It’s possible that over time, Kiner-Falefa can improve at every single one of these things, but at this moment in time, it limits his floor and ceiling. The Yankees are in a position where they do not need to give players like this time to figure it out. They have financial resources and talented prospects. I know it’s unlikely that he loses his spot this year, but my goodness, stop telling us things like he is a top 5-7 defensive shortstop. I don’t care what your internal metrics say. Watch some video and get back to me.