Here's Why Adam Plutko Featuring His Curveball More This Year Is A Good Idea for the Cleveland Indians

T.J. Zuppe

Most exchanges between players and reporters begin with a canned greeting of pleasantries. Adam Plutko's began with a quip about the media looking a lot less tan than when he last saw them.

Boom. Roasted. Plutko's first curveball of 2020. And there might be more to come.

There's good reason for that — the pitch, not the zinger. His curveball was his most effective pitch last year, inducing the lowest expected weighted on-base average of his arsenal (.191), well below the league average for curves last year (.269).

That's an important metric, as xwOBA takes into account the quality of contact (exit velocity and launch angle), strikeouts and walks, giving us a glimpse below surface level.

Admittedly, xwOBA doesn't necessarily tell us why a pitch was good, but it helps strip away some of the luck or defensive contributions which could cloud outcomes.

Given that Plutko's curve also generated the lowest xwOBA of pitchers currently on the staff (minimum 150 pitches), it's safe to say something was very right about it. But, at the same time, something was also very wrong.

"We had good production from (the curveball)," Plutko said, "but I only threw it 11-12 percent of the time."

Actually, according to Statcast, Plutko only threw his curve 10.6 percent of the time last year, the lowest rate of his four pitches. His four-seam (54 percent), slider (24.2 percent) and changeup (11.2 percent) each received more attention.

That doesn't seem like an ideal strategy.

But as for the good news: He's recognized the issue and appears ready to remedy it.

*Plutko’s curveball has entered the chat*

Plutko posted an unspectacular 4.86 ERA and 5.23 FIP last year, but he was also able to string together a pleasant run of 12 starts last season, stretching from July 20 to Sept. 22. During that time, he posted a 3.53 ERA.

However, his final outing of the campaign skewed his overall numbers, as an eight-run start against the eventual World Series Champions raised his season ERA from 4.25 to its final mark.

The 28-year-old righty now enters spring training without any options, meaning if he doesn't make the club's opening day roster in some capacity, he could be seeking employment elsewhere.

In an effort to stake claim to one of the Indians' rotation spots, Plutko spent a chunk of his offseason focusing on ways to make himself "more dynamic," which certainly includes a focus on his curve.

"Kind of like what (Shane) Bieber did last year," Plutko explained, "where his fastball usage was at an all-time low and you saw his strikeout rate increase and increase and increase. Maybe that’s something we look to try to capitalize on."

Focusing on throwing your best stuff isn't exactly a new concept. We’ve seen more and more pitchers get away from establishing their hittable fastballs in favor of hurling their filth at opposing hitters. But, according to Plutko, it expands beyond just tossing fewer heaters.

"We retooled some mechanics," said Plutko, noting some changes made to how his lower half moves through his delivery. "As far as actual pitch development, worked on the curveball quite a bit. If there was any pitch we worked on, it was probably the curveball more than anything."

Time will tell if those adjustments prove fruitful, but the fact that he's recognized what others are doing to get the most out of their ability and seems willing to adapt is a positive step. And if Plutko was going to pick a pitch to focus on refining, the curveball presents a good canvas.

Plutko's curve ranked in the 93rd percentile in spin rate last season, sandwiched between Charlie Morton and teammate Carlos Carrasco. That's terrific. 

But despite spin that would make your washing machine jealous, it’s interesting that just 55.8 percent of it translated into movement, something Baseball Savant calls active spin.

His active spin on the curve was a bit higher in 2018, and that version did demonstrate a slightly above average vertical break. That differs from his 2019 breaking ball, which was 5 percent below average in vertical break. 

Vertical movement vs. avg
Avg. velocity
Active spin
Whiff rate

2018 Curveball



75.4 mph



2019 Curveball



77.3 mph



Having more or less active spin isn't necessarily good or bad -- remember, whatever Plutko was doing with his curve in 2019 seemed to be working from a results standpoint.

But this exercise does show that an increase in active spin for Plutko in 2018 happened alongside some additional curve vertical drop. Perhaps with some tweaks, he can even better utilize his elite ability to spin it.

Another factor that led to the increased production of the curve in 2019 was the fact that he threw them more often to righties than he did in 2018, a good choice given that right-handed hitters slugged just .276 against it in 2019 compared to lefties (.500), per Brooks Baseball.


Another encouraging trend was its location in comparison to his fastball. 

Plutko's heater isn't a head-turner in velocity or spin, but it does generate more ride (essentially, it doesn't drop as much as the average fastball), which means utilizing it up in the zone can have benefits.

Specifically, the four-seamer generated 12 percent more "rise" than the league average in 2019, and over the final two months, he threw it higher up and out of the zone at an increased rate.

Fastball Location Prior to Aug. 1
Fastball Location After Aug. 1

At the same time, he started doing a better job of burying his curveball down and out of the zone in the final two months.

Curveball Location Prior to Aug. 1
Curveball Location After Aug. 1

Fastballs up. Curveballs down.

Seems like a good plan, and the curveball numbers back it up (and before you ask, yes, the Aug. 1 date is an arbitrary point to select, but it also gives us the exact same amount of curveball results and nearly the same amount of fastballs thrown on either side of that date).


If Plutko can expand on that plan, results might follow. His ability to generate elite spin might suggest room for additional development, and he was already doing a few things to better accent the breaking ball last season.

To hold off promising youngsters like Aaron Civale, Zach Plesac, Logan Allen, Tristan McKenzie, Jefry Rodriguez and others to maintain his spot, it will all need to translate into more consistent success.

"I’m coming in and trying to be the best version of myself," Plutko said, "and put that all out on the field and hopefully that’s good enough. If it’s not, then that’s baseball and I go elsewhere. But I’d love to be in Cleveland. I love it here."

Even if it's tough to maintain a tan.

Comments (1)
T.J. Zuppe
T.J. Zuppe

I meant to note this on an earlier article, but if anyone ever reads through a piece and doesn't understand any of the new advanced metric lingo or has a question about modern stats, ask away and I'll try my best to translate it or provide a place for you to get more information. Thanks for reading!