Taylor Jungmann and Diminishing Marginal Utility

When faced with batters on base, Milwaukee Brewers righty Taylor Jungmann goes to his sinker more and throws lower in the zone. He hasn’t given up a home run on the sinker, and the pitch produces ground balls nearly three-quarters of the time. So why doesn’t Jungmann go to the sinker more often?

“What makes the sinker better is that I don’t throw it as much,” Jungmann told me before a game against San Francisco. “It makes it that much more effective because they aren’t looking for it. If I threw it every single pitch, my four-seamer would be better.”

Right now, Jungmann has found the right uses for his sinker. If he used it more, he’d get less value from each additional sinker. This is what makes evaluating pitches by their peripherals so difficult, especially in small samples. Sure, Mat Latos has gotten six whiffs on 24 changeups this year — for a percentage that’s almost twice the average changeup whiff rate — but that doesn’t make the pitch good.

In Jungmann’s case, learning to use the sinker with runners on was a big deal. He had actually gone away from the sinker after college because of a move on the rubber.

He moved on the rubber to make his breaking ball tougher on left-handers. “Regardless of how much spin you put on the ball, just being that far over and coming from that slot that I do, it creates more of an angle on the breaking ball,” Jungmann said of moving to the third-base side of the rubber. Despite a curve that doesn’t have plus velocity — it averages 76 mph, while most plus curves by whiffs average over 80 mph — Jungman is getting whiffs on one in five curveballs this year, almost double the league average.

The effect is exaggerated when Jungman throws to a lefty. That curveball looks like it’ll never make it to the zone. Jungmann, a righty, described himself as a “big, old pitcher stepping across his body and throwing from way over here.” He says the pitch is “coming to your back foot, and it’s moving how much before it even crosses the plate.” Sounds like a pitch you’d give up on.

But moving on the rubber did a number on his command, especially on one pitch. “I just started struggling with with the two-seamer, and I couldn’t command it very well, and I went predominantly to the four-seam to get more strikes,” Jungmann said of his transition from college (where he worked from the first-base side of the rubber), to the pros.

The movement of the pitch here might the problem. The sinker moves more to his arm side than any other pitch he throws. By moving to the third-base side of the rubber, he might find it hard to find the zone with a pitch that’s starting out of the zone when it leaves his hand. With runners on, Jungmann’s prioritizing soft contact over the swinging strike, and he’s less concerned with hitting the zone. (The league walks batters almost three times more often with batters on base as they do with nobody on.)

Ryan Romano did a great job showing the change in Jungmann’s heat map with runners on, which also seems relevant here. Jungmann said that, with runners on, he was “just bearing down a little bit, making sure the ball is down, and definitely going to the sinker a little more just because I’m trying to induce the double-play.” Updating Romano’s heatmaps for bases empty (left) and runners on base (right), the effect is subtle.

With nobody on base, Jungmann uses the four-seamer for more strikes because he commands it better. His four-seamer is a ball 33% of the time; his two-seamer is a ball 43% of the time. He admitted to throwing the four-seamer high to set up his curveball, too. But with runners on, the utility of the ground ball means that he goes to the sinker twice as often.

But if he threw the two-seamer more often, things would change. He’d give up a homer, eventually, he laughed. His walk rate would get worse as he’d be missing the zone more often. The sinker wouldn’t get 72% grounders as it does now, and that 2% whiff rate on the pitch would become more meaningful.

So when Trevor Bauer dismisses the fact his curveball has the highest whiff rate among starters, saying, “That’s just because of how I use it, not because of the movement of the pitch,” then you can understand better how complicated pitching is — and how one good pitch thrown infrequently does not automatically beget one great pitch thrown more often.