Dbacks Pitching Development Has a Very Specific Type

(And it might be the most predictive organizational signature we’ve ever seen)

Over Thanksgiving break, I went down a rabbit hole looking at the young Diamondbacks arms I’m most excited about for 2026. What started as casual curiosity turned into one of the wildest statistical coincidences I’ve ever stumbled across. We all remember the Merrill Kelly trade at the deadline. It brought back three intriguing pitchers. Kohl Drake immediately grabbed the top-prospect label, and David Hageman stole the headlines with his electric AFL stuff and sky-high upside projections. The third arm? Mitch Bratt. Quietly added to the 40-man roster a couple weeks ago ahead of the Rule 5 draft. No fanfare. No buzz. Just a 22-year-old (he turned 22 in July) who will enter 2026 as the youngest player on Arizona’s entire 40-man.

I decided to take a closer look. I was not ready for what I found. On the surface, Bratt’s 2025 line is already eye-popping: 122 innings in Double-A (split between the Rangers and Dbacks affiliates), 3.38 ERA, and an MiLB-leading 148 strikeouts. The number that stopped me cold, though, was his 7.05 K/BB ratio. For the uninitiated, K/BB is one of the single cleanest predictive stats a pitcher can post — it measures the two skills that travel: missing bats and throwing strikes. ERA and WHIP get warped by defense, park effects, and BABIP noise. K/BB cuts through all of it. A K/BB that starts with a 7 is absurdly rare. So my curiosity got the better of me and I went to FanGraphs and started filtering the last decade of Double-A seasons to see just how rare.

Here is what I found: Over the last decade, there have been just 21 AA pitchers to eclipse the 6.5 K/BB mark. Of those 21, there are some remarkable names like Luis Castillo, and some rather unremarkable ones. The unremarkable ones were more heavily command pitchers who had such high K/BB ratios due to their freakishly low BB rates but didn’t necessarily get much swing and miss. So I wondered, how many players in the last decade of AA baseball have had a 7 K/BB and at least a 10 K/9? This is where things got uncanny!

In the last decade of AA baseball, there have been exactly 2 pitchers who have had at least 7 K/BB AND at least a10 K/9. Mitch Bratt… and Brandon Pfaadt (2022). That’s right — the only two Double-A pitchers in the last ten years to pair a 7+ K/BB with double-digit strikeouts per nine are Mitch Bratt and the same Brandon Pfaadt who was throwing meaningful innings in the 2023 NLCS a year later. Oh, and Pfaadt was almost two full years older when he did it.

I thought that was the story. A perfect comp: the left-handed, younger version of Brandon Pfaadt. Then, just for fun, I ran the same filters at Triple-A. I couldn’t believe what I was seeing for a second and so I ran the filter again. Same result. In the last decade across AA and AAA combined, exactly three pitchers across all organizations have posted ≥6.5 K/BB and ≥10 K/9.

Mitch BrattBrandon Pfaadt and…..Zac Gallen!

Three pitchers. One decade. All three in the Diamondbacks organization in 2025.

At that point it felt like the Dbacks front office and I were using the exact same FanGraphs custom leaderboard. This isn’t coincidence — it’s a screaming neon sign of a development philosophy: find pitchers who dominate with both stuff and command, then polish them to maximize their full potential. Potential that many may have overlooked. Here’s the full trio for comparison:

Bratt — two years younger than Pfaadt at the same level, a year younger than Gallen at a higher level — put up the best underlying season of the three according to FIP and xFIP. And he did the second half in Amarillo, quite possibly the most hitter-friendly park in the minors, where he posted a 3.33 FIP and an absurd 2.55 xFIP. Stuff-wise, Bratt fits the Gallen/Pfaadt mold perfectly: elite 70 grade command of a deep, varied mix. The one knock you’ll hear is fastball velocity — he sits 89-92. But he pounds the top of the zone with late life, and the pitch plays way up. It is also worth noting the pitch has trended up since arriving in Amarillo touching 94 in 1 start. His slider spins at ~2,800 rpm (MLB average is 2,430-2,530), already big-league plus. Put it all together and Mitch Bratt’s 2025 season isn’t just good — it’s historically predictive. A unicorn 10.9 K/9 and 7.05 K/BB at age 21 is an eerily similar DNA that produced a Cy Young third-place finisher in Gallen, and the breakout postseason hero just a year later that no one saw coming in Brandon Pfaadt.

The Dbacks didn’t just acquire another arm at the deadline. They acquired the third member of one of the most exclusive statistical club’s in the last decade of the upper minors — and he might be the best of the bunch. Buckle up. Mitch Bratt could be a name we’re all saying a lot in 2026 and beyond.