George Kirby’s slider shows improvement in most recent outing

Don’t be deceived by last night’s middling results; George Kirby is on the right track

George Kirby’s line from last night’s game might not look impressive—just five innings pitched, with two runs surrendered on eight hits and just three strikeouts. He threw 95 pitches in those five innings, bloated by a 30-pitch first inning that was extended by a misplay by J.P. Crawford (ruled a hit, but J.P. would be the first to tell you he should have had it).

That lengthy first inning did damage Kirby’s pitch count, but he wasn’t exactly being hit hard: the damage was off three singles against him, one on an ugly swing by Rutschman in a 1-2 count, and none with harder than an 86 exit velocity. Postgame, Kirby noted how many of the hits were on pitches he thought he’d executed well that the aggressive Baltimore hitters had been able to get bat to, but overall, he was pleased with his outing.

“I think I did a lot better job this week making my pitches. I’d still like to get ahead a little more but I thought this was a great step in the right direction.”

Kirby came up with 11 whiffs in yesterday’s game, one more than in his outing against the Nationals on May 28th. But Kirby did a significantly better job limiting hard contact in last night’s game, giving up no home runs and no extra-base hits, and not even many hard hit balls. Unlike his last outing, when he hung a slider in the middle of the plate in a 2-1 count for Luis García Jr. to demolish (110 EV and 404 feet), Kirby was able to find more consistency with the pitch, leading to better results.

Here are the sliders Kirby threw against the Nationals. They ended up way too much on the plate, and more than that, all over the plate.

Here are the sliders he threw to the Orioles. You can start to see a more consistent shape and location with the pitch:

Now let’s look at the sliders where Kirby got either a called strike, a whiff, a foul ball, or an out:

So we have a pretty clear band of success where Kirby’s slider can be thrown for strikes, specifically to the lefties, and Jackson Holliday taking a rip at a pitch at his kneecaps. Speaking of which, let’s watch that:

As Bryce Miller said the other day, feel pitches like the slider and splitter can take longer to come back, as opposed to fastballs (and curveballs, which are gripped like fastballs). Kirby threw just five splitters last night, which generated three swings, all foul balls; he threw about twice that many curves, so still under his normal season amount (about ~15% for each pitch). Instead, Kirby leaned heavily on his fastballs to deal with the lefty-heavy Baltimore lineup; the sinker was an especially strong weapon, and he went to it often.

But hopefully the improvement in his slider location will buoy Kirby’s confidence in his secondaries as he continues to work back from injury. And as to that, Kirby said the most important thing to him postgame was that he felt physically fine after throwing 95 pitches, something that shouldn’t go without notice, either.