Why Griffin Jax Would Work as a Starting Pitcher
Moving Griffin Jax to the starting rotation wouldn’t just be a role change. It would be another calculated bet on upside.
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Griffin Jax debuted as a starting pitcher in 2021 after being selected in the third round of the 2016 draft out of the Air Force Academy. It did not go well.
Across 18 appearances (14 starts), Jax logged 82.1 innings to the tune of a 6.37 ERA, finishing as a -0.8 fWAR player. The Minnesota Twins quickly scrapped the idea of him as a starter, and over the next three seasons (2022–2024), Jax reinvented himself as one of the more effective relievers in baseball — culminating in a 2.6 WAR season in 2024.
Following a deadline deal amid a Minnesota firesale, Jax landed with the Tampa Bay Rays, where the results have been mixed. He impressed in a small sample after the trade, striking out 12.16 batters per nine across 20 innings with a 3.61 ERA.
But early returns this season have been less encouraging, including a blowup outing in Milwaukee against the Brewers in which he allowed five runs (three earned) without recording an out.
Last Sunday, however, the Rays deployed Jax in a different role — using him as an opener against his former team. He responded with 2.1 innings of scoreless ball, allowing just one hit and one walk.
That usage raises an interesting question: are the Rays toying with the idea of stretching Jax back into a rotation role?
And more importantly — why would they, given how disastrously that experiment went in 2021?
There might be method to their madness.
Why It Makes Sense
The primary reason teams have flirted with the idea of Jax returning to the rotation is the depth of his pitch mix. Jax throws five pitches at least eight percent of the time — a rarity for a reliever — and it’s a group led by his devastating sweeper.
The pitch kills almost all vertical movement, creating a biting, east-west weapon that he’s comfortable deploying against hitters from either side of the plate. It serves as his primary out pitch against right-handed hitters and is one of the better bat-missing sweepers in the game.
From there, the mix branches out with intent.
He pairs the sweeper with a four-seam fastball that he leans on more heavily against left-handed hitters, while also mixing in a sinker that he deploys primarily to righties. The sinker gives him a second fastball shape — one that runs in on right-handed hitters and, when executed properly, generates ground balls at a high rate.
Against left-handed hitters, Jax’s most-used secondary is his changeup. It’s a pitch that fades away from barrels and acts as a natural counter to hitters gearing up for velocity or sweep. It also gives him a reliable weapon to neutralize platoon advantages.
The curveball functions as a true “eye-level disruptor,” mixed in sparingly to lefties to change vertical planes and introduce a north-south element to an otherwise east-west dominant arsenal.
This is what separates Jax from the typical sweeper-heavy reliever.
Most pitchers who lean heavily on a sweeper profile tend to be platoon-dependent, deployed in specific situations to maximize matchup advantage. Jax, however, has built an arsenal that can attack hitters from both sides of the plate with distinct movement profiles and intent behind each pitch.
The biggest hurdle in a potential transition will be fastball execution.
Jax has added roughly an inch of induced vertical break while cutting about five inches of horizontal movement since his 2021 debut. Even with those changes, the four-seam fastball is not an elite pitch on its own — and in a starting role, where velocity may dip over longer outings, command becomes critical.
This is where the sinker becomes particularly important.
Having a second fastball shape — even if neither grades as elite — forces hitters to account for multiple movement profiles. It also allows Jax to generate weaker contact and manage pitch counts more effectively.
In 2021, Jax was a true fly-ball pitcher, running just a 32.2% ground-ball rate. Since then, he’s posted a ground-ball rate north of 45% every season, including a 56% mark in 2026. Opponents averaged a -7 degree launch angle against his sinker in 2025, and both the sinker and changeup have consistently driven negative or near-zero launch angles.
On top of that, his two primary secondaries — the sweeper and changeup — are legitimate bat-missing weapons. Both posted whiff rates north of 45% in 2025, giving him two distinct pitches that can finish hitters in different ways.
That combination — elite swing-and-miss paired with the ability to generate ground balls — is exactly what allows pitchers to navigate lineups multiple times.
Jax will need to improve execution with both fastball variants to make a full transition work. But the foundation is already in place. A legitimate five-pitch mix, with weapons against both right- and left-handed hitters, is why the Minnesota Twins were once so bullish on his potential as a starter — and why the idea may not be dead just yet.
Jax’s Role For the Rays
The Tampa Bay Rays are off to a strong start at 18–12 through the first month of the season. So, why even consider a move like this?
The answer comes down to a combination of depth, preservation, and internal reinforcements.
At the top of the rotation, the Rays are leaning on Drew Rasmussen and Shane McClanahan — both high-end arms with well-documented injury histories. Behind them, the picture becomes far less stable.
Jesse Scholtens, a 32-year-old journeyman, has never eclipsed 85 innings in a season. Steven Matz and Nick Martinez are both in their mid-30s and better suited to managed workloads than full-season volume.
Even with Ryan Pepiot and Joe Boyle expected back from the IL, it would be very on-brand for Tampa Bay to carefully manage the innings of Rasmussen and McClanahan to ensure they’re available deep into the season.
That’s where Jax comes into play.
In the short term, he doesn’t even need to fully transition into a traditional starter to provide value. A piggyback or long-man role would allow the Rays to steal innings, reduce strain on their veteran arms, and create flexibility within the rotation.
At the same time, the bullpen is positioned to absorb that shift.
Garrett Cleavinger is expected to return this weekend, providing an immediate boost. If Boyle’s command continues to waver, he could quickly transition into a high-leverage relief role, adding another power arm to the mix.
There’s also a longer-term wildcard worth monitoring: Brody Hopkins. Ranked as the No. 38 prospect by Just Baseball, Hopkins possesses some of the most electric raw stuff in the minors. However, his command remains a major question mark — evidenced by a 7.40 BB/9 across 24.1 innings at Triple-A. If those issues persist, a bullpen move could accelerate his path to the big leagues and give Tampa Bay yet another high-octane relief option.
Looking ahead, Jax’s situation becomes even more intriguing.
He remains under team control through 2027, and if he flashes even partial viability as a starter, his value changes dramatically. A team like Tampa Bay — always operating with an eye toward asset optimization — could unlock significantly more value from Jax as a swingman or starter than as a traditional reliever.
There’s a very real scenario where Jax provides meaningful innings in 2026, helps stabilize the pitching staff, and simultaneously boosts his market value beyond what it would be in a bullpen-only role.
We are a long way removed from the Air Force cadet who struggled as a starter in 2021, but Griffin Jax now has a chance to make what was once old, new again.
Final Thoughts
An advanced, diverse pitch mix — paired with a unique situation in Tampa Bay — has created an opening for a dominant relief arm to absorb meaningful innings in a starting role. It’s not a traditional path, but it’s one that aligns with how the Rays operate.
There’s a real chance Tampa Bay opts to weather the storm with spot starts from Triple-A arms until reinforcements like Boyle and Pepiot return to full health. That would be the conservative route.
But there’s also a more aggressive — and potentially more rewarding — path.
If Jax proves capable of handling extended outings, he could do more than just stabilize the staff. He could help the Rays sustain their strong start and position themselves as legitimate postseason contenders, all while keeping their rotation fresh for the sprint that matters most.
For Tampa Bay, it wouldn’t just be a role change. It would be another calculated bet on upside.
Stats were taken prior to play on April 29.
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