Isiah Kiner-Falefa and the mark of a turnaround

It’s no secret that a lot of criticism has been pointed in Isiah Kiner-Falefa’s direction over the course of the season. Among the Yankees’ fanbase, he can often be seen as a woeful placeholder for the more heralded prospects (like Oswald Peraza and Anthony Volpe). This sentiment has not gone away as the season has progressed, and has even been reinforced by his relatively middling triple stat line of .263/.315/.331 with a fairly poor wRC+ of 86.

In contrast to his rather middling rest of the season, Kiner-Falefa has positively rocked during September. In this stretch, his triple slash line sits at a much more palatable .270/.341/.419 with a far superior 120 wRC+. Those numbers certainly approach respectability. In particular, his on-base percentage has increased. In previous months, IKF has either posted a good batting average or a good walk rate, usually not both. What can the Yankees make of this turnaround in performance?

The quick and dirty answer remains what it has been for the rest of the season. IKF offers great defense, but relatively little in offensive capability. The longer version is more complicated. His advanced batting statistics remain doggedly mediocre.

Credit: Baseball Savant

Baseball Savant does not think much of Kiner-Falefa’s defensive prowess, but we will be setting that aside in this post, as it’s not the focus. The Yankees seems to believe in his glove, and other places (like FanGraphs and Baseball Reference) are more bullish on his abilities at shortstop. Even disregarding all this, IKF’s performance at the plate does not inspire a lot of confidence.

On the positive side of the equation, Kiner-Falefa does have an expected batting average (.262) in the top 24 percent of the league, and his strikeout rate (13.8 percent of the time) sits in the 91st percentile. Unfortunately, the numbers get much worse from there.

For the year, IKF has just five total barrels with optimal launch angle and speed off of the bat. This gives him a paltry barrel rate of just 1.4 percent of his batted balls. This results in a barrel rate in the bottom one percent of the league. That’s what you call scraping the bottom of the barrel. At the same time, his expected slugging percentage (.333) sits at the bottom 7 percent of the league.

If his numbers still look pitiful, what has led to his surge at the plate? Has he made some much needed improvements to his swing?

I am not an expert on swing mechanics, but my colleague Esteban (who knows a lot more about swing mechanics than me) thinks that Kiner-Falefa might be making some positive adjustments. He suggests that IKF has been somewhat more consistent in his swing posture. He has been falling over his front leg and losing balance less often.

At the same time, Kiner-Falefa also seems to be sitting a little bit back so that he can more effectively hit breaking and off speed pitches. This might explain why he has a 1.333 SLG on off-speed pitches in September. Whether those adjustments stick, or if he relapses is an open question.

IKF is turning up the heat at the most opportune of times. If he can manage to keep this up into the postseason, perhaps he could etch himself a permanent spot in Yankees fans’ hearts as the shortstop for the first championship team in 13 years. However, even if he does so, he is still playing on borrowed time as a Yankee. There are too many options on the roster and in the system to keep playing IKF long-term as the everyday shortstop.

The problem with Kiner-Falefa is not that he can’t provide consistent value, but it’s that his upside is severely lacking. Yes, you can pencil him in to the lineup and expect him to provide a batting average above .250 with 20 steals and under 10 home runs, but that's about it (unless you are on the bullish side of his glovework). With two highly touted shortstop prospects in the system and seemingly ready for the big league, it just does not make sense to play him everyday past this season. Both Peraza and Volpe offer much more potential.

The Yankees have dug their heels in on Kiner-Falefa for 2022, and at this point, there’s no changing the fact that he will be their shortstop in the playoffs. He’s thankfully given us a little bit of reason for hope with his past month of play, but it would still be wise for the organization to take it with a grain of salt and not disrupt their future plans on his behalf.

All cited statistics were active as of the beginning of play on Friday, September 30th.