Every year, a handful of players ranked outside the top 10 in their respective farm systems take meaningful steps forward to improve their stock and vault up prospect rankings. Part of the fun is trying to identify those breakouts before it happens. So today, we’re identifying Diamondbacks prospects who have the potential to make a jump in 2026.

To qualify, a player must rank outside the organization’s preseason Top 10 prospects. All scouting reports are from Baseball America’s 2026 Prospect handbook, which you can purchase here.

You can find Top 30 prospect rankings for all teams here and all breakout candidates here.

Breakout Prospects

Brian Curley, RHP

BA Grade/Risk: 45/Average
Adjusted Grade: 35

Track Record: Undersized and lightly scouted out of high school, Curley ended up committing to Virginia Commonwealth, where he redshirted his freshman year as he recovered from Tommy John surgery. He pitched two seasons there, mostly in relief, before transferring to Georgia. He started the year as the Bulldogs’ closer, worked his way into the rotation and ascended to the Friday night starter’s role. The Diamondbacks, who took him in the third round and signed him for an under-slot $700,000, plan to give him a chance to start, knowing there is a fallback since his stuff would play well in short bursts.

Scouting Report: Curley sat 95-96 mph and touched 100 with his fastball. He gets above-average carry and it plays up further due to a low release height and unusual approach angle. His upper-80s slider has both depth and power. His curveball is more of a top-to-bottom offering, and he also threw a third breaking ball, a sweeper, though the three could blend together. He also has a fringe-average changeup. How the entire package, including his command, which is good enough when the stuff is loud enough, plays on a five-day pro schedule remains to be seen. He is inquisitive, coachable, hard-working and confident.

The Future: Curley’s fastball and slider might jump a full grade in a relief role, so if starting doesn’t work out he should have the stuff to pitch late in games out of the bullpen.

Scouting Grades: Fastball: 60 | Curveball: 40 | Slider: 55 | Control: 50

Jaitoine Kelly, RHP

BA Grade/Risk: 50/Extreme
Adjusted Grade: 30

Track Record: The younger brother of Pirates prospect Antwone Kelly, Jaitoine threw mostly in the upper 80s with a raw delivery and underdeveloped secondary stuff when the Diamondbacks started scouting him in 2023. Liking his size and the way he moved—and the fact that his older brother threw significantly harder despite having a smaller, stockier build—the Diamondbacks signed Kelly for $70,000 on what was a deep projection play. A couple years later, it is looking like a sharp investment. Kelly’s fastball made a big jump in 2025 and he looks like he could have the makings of a future starting pitcher.

Scouting Report: After averaging 88.3 mph and topping out around 91-92 mph in 2024, Kelly’s fastball averaged 92.6 mph and touched 95-96 in 2025. He averaged 17.2 inches of carry and has been up to 7 feet of extension. His best secondary is a kick changeup with good fade that can resemble a splitter. He has a slow, sweepy curveball that grades as below-average; he might need to add a harder, shorter breaking ball that would pair better with his fastball. Kelly has an above-average delivery and arm action and made huge strides in his strike-throwing. He will need to continue to work on his body to maintain athleticism.

The Future: Kelly has a long way to go but has significant upside given his arm and frame. If it all comes together, he has the potential to be a midrotation starter.

Scouting Grades: Fastball: 60 | Curveball: 45 | Changeup: 55 | Control: 50