Paint of the Week: George Kirby slides into second gear

George Kirby had a phenomenal rookie year, with his sub-3.00 FIP putting him in elite company. But a funny thing happened to start out 2023: he lost the ability to miss bats. Through his first six starts, his whiff rate was down almost 10% from 2022, which moved him from a bit below league average (made up for with the soft contact and lack of walks) to almost the bottom of the league.

He was still stingier with walks than Ebenezer Scrooge was with charity, allowing just three free passes in 37.2 innings. But he was also as stingy with strikeouts as Marco Gonzales is with strikeouts, down to a measly 17.6% K%. He was going to need the strikeouts back if he wanted to go from nouveau Kyle Hendricks to a Cy Young contender.

As best as I can tell, the culprit was his slider. Kirby, like seemingly all the Mariners starters these days, is a fastball-first pitcher, who only goes from good to great when he’s got his secondaries working. Last year, when he was competing for Rookie of the Year, he had pinpoint command of his slider. Just take a look at this heat map of his 2022 sliders:

That’s right where you want it, and with remarkable consistency. But he changed his slider coming into this year. The good news is that he made it a better pitch. Already a pitch with above average break both horizontally and vertically (which, I mean, wow), over the offseason he added three inches of depth and two inches of sweep. And he somehow did it without sacrificing any velocity. The bad news is he no longer knew how to get it on the edges. I suspect that he began the year still getting used to its new shape, which made it a little harder to know exactly where to aim it. Through his first six starts, he was regularly catching too much of the plate with it.

That all changed on Tuesday, when he faced a resurgent Rangers lineup. Here he is in the Play of the Week, hitting the corner-iest corner against Marcus Semien, Texas’s best hitter, who has no idea what to do with it.

Suddenly, the strikeouts were back, punching nine tickets on Tuesday to go with the classic Kirby sidekick, which I like to think of like a Star Wars droid: Zero-Bee-Bee. Getting the slider on the bottom rail (though still occasionally missing in the zone), seemed to me to make all the difference.

Kirby’s slider may only be his fourth-best pitch, but if he can keep the new movement while regaining his command of it, it’s a hell of a fourth-best pitch. It’s what I’ll be watching for most closely as he faces the Red Sox tonight.

Honorable Mentions

Jarred all day every day

I’m trying to exert some self-control, so I’m only going to include one Jarred highlight. I almost went with Saturday’s home run off an Alex Faedo pitch that was both high and inside, a pitch it’s frankly impressive Jarred made contact on at all, much less hit out of the park. But I prefer his making it to third base on a ball hit to left field, especially because this is such a fine piece of hitting, taking a pitch outside and going the other way with it. One of the keys to his breakout has been his refusal to try to do too much with his swing and rely on his baserunning to prop up his ISO.

Logan ties a franchise record

Logan Gilbert would probably be the best pitcher on at least 15 teams, but amid the crowd in Seattle, he’s often barely noticed. Did you know that just six weeks into his third season, he’s already 24th in fWAR in Mariners history? On Monday, he got Félixed for the second time already this season, but etched his name into the history books by striking out seven batters in a row.

Julio gets right (maybe)

This is a bad pitch from a bad pitcher, but Julio needs all the momentum he can get, so we take it.

J.P. continues to be the coolest

Is it just me or does it seem like Crawford saves a disproportionate number of his web gems for the ninth inning?

Jarred keeps the perfecto alive

I lied.