Having Tommy Kahnle is good for a few reasons. First, purely, it’s good to have good pitchers, and with an injured list that already includes so many names, the Yankees will need Kahnle to play a key role. We already touched on that along with his return a few weeks ago, and time since, there hasn’t been much reason to believe that’s any less true.
Another thing from Estevão’s piece — its central topic, actually — that hasn’t changed is Kahnle’s increased reliance on his changeup since his return, as he’s still throwing it a career-high 82 percent of the time, up from 76 percent last year and 52 percent in 2019, his last full healthy season (also in New York). On a more granular level, having Kahnle is good because his changeup gives the Yankees another unique weapon in a bullpen full of unique weapons. Since the 2019 season, he’s leaned on the changeup more than any pitcher in baseball, with only Milwaukee’s Devin Williams even in the same ballpark.
But unlike Williams’, whose “airbender” makes its hay with filthy movement out of the zone, Kahnle powers his dominant offspeed pitch with a tremendous feel for location. It’s pretty nasty on its own, of course — living in the high-80s, it’s one of the 10 hardest changeups on average since ‘19 (minimum 500 total), and at just over 1300 rpm, Kahnle is one of the best in the game at killing spin. Any movement lost from spin may be compensated for by seam-shifted wake effects, and overall, the result is a bowling ball that doesn’t get a ton of side-to-side movement but separates quite nicely from his fastball.
It’s pretty nasty, but it’s not a crazy outlier. What is an outlier is Kahnle’s ability to command the pitch to right-handed hitters like you just saw.
A good right-on-right changeup can be hard to find because if a pitcher doesn’t have a good feel for pronation — manipulating the wrist at release to roll the ball off of the last three fingers, as one does for a traditional changeup — it can be difficult to find any kind of consistent location with it with a hitter in the arm-side batter’s box. And even if a pitcher does have a good feel for pronation, the difference between a well-executed backdoor changeup and one that gets floated right down the middle into a hitter’s barrel is only a few inches. Pitchers who can be this precise with a right-on-right changeup are few and far between.
Beyond simply making him a good pitcher, this route to success adds an important element of balance to the Yankees’ bullpen. Because a changeup is typically most effective against opposite-handed hitters, Kahnle’s ability to make it work against righties has caused him to run essentially a fully neutral platoon split over the course of his career, with a wOBA separated by just a single point. The split is roughly 30 points wider (in the traditional direction) dating back to his re-invention in 2019, but the takeaway is the same: He’s more effective against lefties than your typical two-pitch righty.
If Kahnle remains effective, this dynamic will certainly be a specific boon to a bullpen that currently has Wandy Peralta as its only high-priority southpaw option at the moment. (Apologies to Nick Ramirez.) That’s not necessarily a bad thing in and of itself, as the Astros just won a championship without a lefty reliever in sight after leaving current Rangers closer Will Smith off their roster for the final two rounds of the postseason. But while they’ve seen good results against lefties so far, expected stats think there’s some regression coming, assigning them a .316 xwOBA to their .285 actual wOBA and, more worryingly, a .366 xwOBA on contact compared to the .325 they’re currently running.
It hasn’t come back to bite them yet, but a substantial chunk of that outperformance has come courtesy of Clay Holmes, Albert Abreu, Ron Marinaccio, and Jimmy Cordero, all among the team’s most frequently-used relievers against lefties and most of whom have a history of subpar platoon splits. Michael King’s wide, high-octane arsenal means we don’t have to worry much about him, but it seems that it would be prudent to get ahead of the game and not wait for the regression monster to come for Holmes, Cordero, or Abreu.
The returns of Ian Hamilton (whose slambio plays against hitters of either hand) and, sometime in the second half, Jonathan Loaísiga will help. In the meantime though, Kahnle should be key support to Peralta and King as options that Aaron Boone can trust in more or less any platoon scenario. As likely as not, Yordan Alvarez and Kyle Tucker are waiting at the end of an American League playoff run, and it would be nice to have at least a few guys you can be confident in. Wandy can’t pitch forever! If Kahnle and the aforementioned duo can maintain (and find) their health for the stretch run, the Yankees may be in better shape than they were last October, in spite of the likely difference in record.