Matt Marton-Imagn Images

One Statistical Anomaly Points to Substantial Bounce-Back for Griffin Jax With Rays

Originally posted on Tampa Bay Rays on SI
By Kenneth Teape | Last updated Oct 25, 2025 7:00 AM ET

The Tampa Bay Rays made a few moves ahead of the MLB trade deadline this past summer. However, there was one that stood out because the team looked like sellers, but this move would certainly fall under the buying category.

In search of some help for the backend of their bullpen, the Rays made a deal with the Minnesota Twins. A one-for-one swap was completed, with Griffin Jax heading to Tampa Bay in exchange for starting pitcher Taj Bradley.

In the early going, this looks like a deal that the Rays have won. Despite Jax not yet regaining the dominant form he showed previously with the Twins, he performed at a much higher level than Bradley did.

Through six starts, the right-handed starter had a 6.61 ERA through 31.1 innings. Jax had a good 3.60 ERA through 20 innings of work with 27 strikeouts.

He produced a 0.3 bWAR after having a 0.2 bWAR through his first 50 appearances in 2025 with Minnesota. His ERA with the Twins was 4.50, as his numbers worsened from his lights-out 2024 campaign.

What led to Griffin Jax's up and down 2025 season?

However, when taking a deeper look into Jax’s production, it is easy to see why Tampa Bay targeted him ahead of the deadline and he is set for a raise in arbitration. A lot of his struggles, or what seemed to be a lack of success, can be attributed to bad luck.

With Minnesota, he had a batting average on balls in play of .393. With the Rays, it improved to .333, but that was still well above the league average of .292. For his career, Jax’s BABIP is a stellar .288.

Opponents putting balls into play that in the past would have been turned into outs is a big reason why his ERA was inflated; a lot of his underlying metrics remained excellent otherwise.

In 2025, his overall FIP was 2.51; it was 2.05 with the Twins and 3.59 with Tampa Bay. His strikeout numbers remained elite, punching out 99 batters in 66 innings for an elite 35.0% strikeout rate.

That was a single-season best. Most importantly, he wasn’t issuing walks, either. His 7.4% walk rate was a little higher than his career norm, but still below the MLB average.

Griffin Jax in line for a massive 2026 campaign

As shared by Dustin Teuton of RBLR Rays, pitchers who perform as well as Jax did normally have better luck.

Of all the hurlers with at least 60 innings pitched and a strikeout rate of at least 25%, only Kansas City Royals starter Cole Ragans (4.67) and Devin Williams of the New York Yankees (4.79) had higher ERAs.

If he keeps up the same level of performance, Tampa Bay will be on the receiving end of a monster campaign.

Leaving Jax in the bullpen, amidst some suggestions that he could be stretched out into being a starter, is the right move for the Rays to make.