Carson Kelly Is ABS Monster, Showing Advanced Feel for Challenges

This is the third of four pieces on MLB’s Automated Ball-Strike Challenge System, I think. The next will look at how the stat is affecting the game overall, with an eye toward what Nico Hoerner was saying in the first installment about how ABS opens the road for more influence by robot umps.

ABS was introduced into the major leagues this season and has impacted a great many games already. The good folks at Baseball Savant have been kind enough to log how the players are doing with this new toy, and we’ll discuss that a little more, keeping in mind that this is a Cubs blog and demands focus on the home team.

MLB.com’s Jordan Bastian recently posted an item talking about how good Cubs’ 1A catcher Carson Kelly is, and we’ll also check in on 1B catcher Miguel Amaya. The thrust of the piece was how Kelly’s aptitude for challenging the right pitches at the right times has helped to swing key moments for Cubs, and that, dear reader, is exactly what we are talking about.

“Entering Sunday’s game in Texas, the veteran Kelly led the Majors with an 89% success rate (17-for-19), among catchers with at least 10 challenges this season,” Bastian wrote. “Kelly’s decision-making had led to eight at-bats being flipped to strikeouts — second to only Ryan Jeffers (11) of the Twins. That included two walks turning into punchouts, and three walks overall being eliminated.”

Combined with catchers Amaya and Moisés Ballesteros, the Cubs were tied for third in MLB in overall success rate (70%) in challenges from their fielders (pitchers/catchers).”

Kelly doesn’t instigate the most challenges — that would be William Contreras with 44 through Sunday — but he has created the most runs for his team with his work. His sense of the dramatic has been evident for quite some time. He’s a clever guy with obvious good work habits and a vested interest in doing well, as this is the pinnacle of his career, at 31 years and some change.

“A lot of it is situation dependent,” Kelly said. “It’s knowing when to use them and how sure you are of it being a strike. … So, it’s the certainty level, trusting your eyes and just understanding the situation.”

Sahadev Sharma is on the train also, though the jury is admittedly still out on just how much of this is aptitude rather than luck.

“Whether it is a long-term skill is still unclear,” Sharma wrote. “It will take more games to really figure out what is sticky. Like framing before it, clubs are still learning the nuances of this skill — and whether they believe it really is a skill or trends more toward randomness.

The Cubs have had seven fewer challenges than Contreras. They have won 16 and lost 21 (43%), from the batter’s point of view. They are 32-13 (71%) as the fielding team. Let’s break that down a little, concentrating on Kelly. Dillon Dingler has the most overturns versus expected (18), followed by Hunter Goodman (13.8). This is based on a Tom Tango system and seems overcomplicated, as stats are wont to be (and why I don’t trust most “advanced” stats). The won/lost data is good for me.

The best percentage in that area is owned by Kelly, who is third in the above listing. That ranking is arguable, but nobody is going to gainsay 90% accuracy. For the sake of context, Contreras is at 55% with his volume-based strategy. There are a few guys with 100%, but they’re not regulars. Dingler and Mitch Garver are both at 83%, though Garver has only challenged 12 calls as Seattle’s second catcher.

Amaya is 25th at 13 of 22 (59%), which is neither great nor bad. Ballesteros only has one challenge, which he lost, but he has shown a keen eye at the plate as a hitter. More than just knowing what to challenge is having a feel for when to tap the helmet, as Kelly noted, and that may be something he can teach his understudies over time. The Cubs’ 71% success rate puts them behind the Tigers and Dingler at 83%, but the Cubs have had more challenges from more people.

Kelly’s standout performance with this new concept is striking, hence the recent uptick in articles (CI was first). As mentioned at the beginning, you can expect at least one more piece on this topic as well all continue to get more familar with its place in the game.