Breaking arms brings Dylan Seaz to the Blue Jays

As a 29-year-old who joins the Toronto Blue Jays with more than 1,000 MLB innings under his belt, it’s fair to describe Dylann Seaz as a finished product.

The Blue Jays wouldn’t have given the right-hander the largest free-agent deal in franchise history on prospect alone, and Cease’s 20.0 fWAR through 2021 — fifth-highest among all pitchers — is more than enough proof of concept for his status as a top-of-the-rotation starter.

At the same time, the Blue Jays are paying Seaz for his help from here, not his past accomplishments. The future they have invested heavily in will affect how they are able to work with him to enhance his already impressive talents.

In recent years, the Blue Jays have had notable success getting the most out of high-K, high-BB pitchers with a similar statistical profile to Cease, such as Robbie Ray and Yusei Kikuchi. Although there is no one-size-fits-all approach to improving player performance, these experiences are instructive. Toronto doesn’t have a fixer-upper on its hands, but it wouldn’t go all in without some thoughts on Seas on what he could do differently in a Blue Jays uniform.

These ideas can take a variety of forms, from grip and mechanical adjustments to a change in philosophy on aggression in the strike zone. Especially with Seaz, one of the most exciting possibilities is for the right-hander to broaden his arsenal a bit.

Seaz threw six different pitches in 2025, but he’s best known for the fastball-slider combo he’s used at least 80 percent of the time in each of the past four seasons. Since 2024, no other pitch he’s thrown has even had a 10 percent usage rate. He hasn’t been a two-pitch pitcher in the Kevin Gausman mold, but he’s not far off.

This approach has been undeniably effective overall, but some of Cease’s most notable weaknesses seem to be related to his reliance on his top two weapons. His distribution of plots is a clear example of this. In his career, left-handers have hit .239/.325/.406 against him (roughly what Nathan Lukes managed in 2025) while righties have slashed .211/.249/.349 — good for the same OPS Andres Gimenez produced in the worst season of his career this year.

He’s not completely ineffective against lefties, but they can bat more comfortably against him, focusing on them instead of chasing his upper-strikeout offense. In most cases, when a starter throws two pitches the majority of the time, their secondary offering is a more vertically oriented pitch, such as a splitter (Gassman), a curveball (like late-career AJ Burnett) or a changeup without too much arm-side feed (like Marco Estrada), that is platoon-neutral or close. The fastball slider is a combo that invites opposing managers to stack their lineups with lefties.

Seaz isn’t the first pitcher to produce at a high level despite some platoon weaknesses, and he’s made efforts to mitigate the problems in recent years. In 2024, he played with a cutter early in the season until he allowed a home run in May. He used it only twice after that and stored it in 2025.

The veteran starter has also featured a changeup throughout his career, but his swing has been far below average, and he’s gotten to it less and less over the years.

There’s one pitch hidden in his repertoire of tertiary pitches that might help change the paradigm against left-handed hitters — and that could increase his unpredictability overall.

Seaz’s nickel curve is technically his third pitch, but he threw it 8.5 percent last season, and it may deserve a bump in usage. While the pitch hit hard in 2025 (.576 SLG), due to its excellent swing profile, it also produced an excellent whiff rate against lefties (39.7 percent).

The right-hander has a vertical spacing that is above average (+5.7) inches, with a below-average horizontal spacing on the glove side (-6.0 inches). The end result is a pitch that falls off the table with a relatively clean 12-6 process.

By skipping too many curveballs and avoiding running towards the glove in left-handers, this is exactly the type of pitch that can help them get rid of them. The small sample results are not impressive, but it seems to be a location problem with too many hangers in the mix at the moment:

Seaz’s curveball isn’t the only one of his lesser-known pitches that may have some hidden potential. It introduced a cleaner in 2024 with some unique movement features.

Notably, his offensive vertical distance is above average (plus-9 inches) than any of the 161 pitchers who threw at least 100 homers last year. Although his horizontal movement is slightly below average, it still has more glove-side movement than Seaz’s traditional slider, and does a great job of getting away from right-handed hitters.

Seaz threw just 106 sweepers last season, but produced seven strikeouts while slugging just .095 against those opponents — good for a plus-4 run cost. This evolving proposition isn’t very useful against the left, but its development could make the new Blue Jays more of a headache for the right.

Characterizing it and the curve a little more can also be helpful to stop facing another problem: a relatively wide time-order distribution that has always dogged him – but was especially ugly in 2025.

Last year’s numbers may be more statistical noise than anything else, but the overall pattern is there. Seaz is far from the only pitcher that hits hitters seem to do better with more at-bats, but his heavy reliance on two pitches can make him easier to adjust to. Giving hitters a wide array of looks may make it difficult for them to become familiar with his stuff. The biggest knock on Seaz is that he sometimes pitches deep in games, and the third time through the order will help him perform better.

Pitch-mix tweaking is tricky business, and any suggestion that Seaz should clean up his curve more is a call for him to use his slider/fastball combo less — and riding those two pitches earned him just over $200 million. During his tenure in Toronto, Seaz and the Blue Jays will undoubtedly spend a lot of time looking at how to make him the best pitcher he can be.

What should encourage the team is that the process doesn’t have to start from scratch. Cez already has some interesting weapons in his back pocket that could help him solve some of the problems he’s faced in recent years.