Brian Bannister has not been one to undersell his charges since joining the White Sox organization, but it raised an eyebrow when he referred to a recent bullpen session with Jake Eder as "kind of a breakthrough."
It's what Eder's development has called for since arriving in the White Sox organization. The previous front office, in one of its more divided moments, dealt a resurgent Jake Burger at the height of his powers on the notion that Eder would soon return to his pre-Tommy John surgery prospect glory. Eder walked 30 batters in 35 innings last year between Double-A and the Arizona Fall League instead.
Even now as part of a vaunted Birmingham Barons rotation that carried the team to a first half division title, Eder's progress has been more gradual. He is back to striking out hitters at a righteous clip (27 percent), and his 9.1 percent walk rate is his lowest as a professional. But by bad luck (.360) or a sudden spike of six home runs allowed in June, he sports a 4.93 ERA (albeit a 3.61 FIP) in Double-A while taking up a 40-man roster spot.
Yet Eder speaks of the session in equally glowing terms.
"We only spent 20 minutes together during my side and we were able to tweak those two things," Eder said by phone. "The slider and the changeup, and that's a game-changer."
"Just how you work as a more east-west pitcher," Bannister said of what he stressed to Eder. "A lot of guys throughout the college ranks here in the past were trying to chase vertical movement on the four-seam fastball. I’m very confident in guys who have more of an east-west component or more of a two-plane component. Teaching them how to pitch in that style.
"I think we were able to do some things with his grips and his shapes and kind of the concepts that will allow him to grab a little more movement or be a little more consistent. You saw his year a few years ago before he had Tommy John, he was one of the better pitchers in the minor leagues. He has some pedigree, and power lefties that can spin the ball -- I’ll take them all day."
Eder will turn 26 in October, but Bannister's assertion that tall left-handers with the potential for plus fastballs and breaking balls are worth as much patience as is required is a theme he hits upon consistently. Eder's lower-slot delivery only enhances the degree to which his fastball plays up in the zone due to the flatter attack angle it creates, and that has been a major part of his emergence in professional baseball.
But in saying that Eder is just continuing to embrace the east-west nature of his delivery and arsenal, Bannister might have actually sold this one a little short.
"He was basically telling me that I'm a supination guy," Eder said. "I had never even thought about throwing a changeup that way. No one had ever said anything to me about it. I was never was taught anything like that. I'd say it's a huge change but when you look at it, at the same time it isn't. Because I'm essentially doing less. I'm just throwing it and not trying to do anything with my wrist."
Maybe supination/pronation has not been discussed a ton with White Sox prospects, but the distinction is essentially which direction a pitcher is more naturally inclined to rotate their wrist upon release. Pronators are typically able to induce a lot of arm side movement on their changeups, whereas supinators are well-suited to rip off a breaking ball that sweeps hard to their glove side. Eder's two-plane slider has long been the highlight of his profile, and his changeup has shown flashes in the past. But in being pushed to embrace what he does naturally, Eder feels enabled to show the consistency he's never previously been able to sustain.
In the same vein as Garrett Crochet and Noah Schultz, Bannister felt Eder was a good candidate to add a hard cutter as a versatile and easier to command bridge between his trademark slider and his fastball. With his natural ability to manipulate glove side spin, Eder found the 86-88 mph offering to be an intuitive fit.
"It just gives me a different look with something that looks like a fastball for a long time, but isn't," Eder said, "whereas the bigger breaking ball is a really depthy pitch. If I need a swing and miss in a situation I can go to that one. And I can get ahead in the count with the hard one."
With the vertical action on his fastball and the level of depth on his slider, Eder feels he can work up and down in the strike zone, and his cutter immediately offers a tool for working inside on right-handers. But with Eder's supination bias, the real trick is finding an offspeed pitch that can move to his arm side to complete the picture.
In the past, Eder has tried to pronate his wrist to trigger arm side movement, which has not only been inconsistent but is effort-laden enough that he's wondered if the highest level hitters could pick up on it as a tell. What Bannister suggested was less a grip change, but to orient the ball to use seam-shifted wake for arm-side movement, while maintaining his normal manner of throwing.
"The grip is basically the same," Eder said. "He taught me about some of the seam-shift stuff where I'm throwing it and keeping my hand supinated, almost like throwing a cutter sort of. But then the seams catch and it ends up going the opposite way."
Eder had 10 strikeouts over six innings of one-run ball soon after the bullpen session that backed up the assertion that he was a new man. His two subsequent outings have been the sort of choppy affairs filled with whiffs that had previously suggested big raw talent with significant development left to traverse.
When Eder arrived to the White Sox, the work to be done in cleaning up his lower half mechanics -- pelvic posture, hip rotation, riding on his back leg -- was voluminous enough to end his 2023 regular season early and prepare him for the Arizona Fall League. He admits he's still getting used to a new arsenal and where his new points of strengths and weakness lie in the strike zone. Yet being in a place to add and incorporate new pitches and have them feel natural and suited to him is a respite from years of injury rehab, mechanical tinkering and striving to rebuild the effectiveness he had before Tommy John surgery.
"My big breaking ball, that hard slider and then the changeup, my wrist is essentially in the same position in all three pitches, which makes it very simple and I don't have to think about anything but changing the grip," Eder said. "I feel really good. I feel like I've got command of those four pitches. They're all good and they're all weapons. In 2021, I really threw two pitches only. I've taken a little bit of time to learn how to use them and in what spots, which is best. But ultimately I'm a way better pitcher now than I was."
