Cox was the Rockies’ second-round pick in 2022, but had Tommy John surgery in 2023 and is still making his way back
26. Jackson Cox (103 points, 15 ballots)
Cox was Colorado’s second-round pick in 2022, 50th overall, out of a rural high school in Washington state — the only high school player the Rockies drafted in that class. To get Cox out of his commitment to Oregon, the Rockies signed the 6’2” righty starter for a $1.85 million bonus — well over the pick’s $1.54 million slot value.
Cox’s calling card as a prospect is his 3,000+ RPM curveball, described as a slurve with “deep and late bite” which the 21-year-old paired with a low- to mid-90s fastball and a developing change-up in a repeatable delivery. When healthy. Which he hasn’t been, though entering 2025 we should finally see Cox again.
Cox was assigned to Low-A Fresno in 2023 for his professional debut, where he was 2.9 years younger than league average. The Rockies handled Cox carefully, never allowing him to go past four innings in a start or 65 pitches an outing in his ten games (nine starts). Nonetheless, Cox suffered an injury that required Tommy John surgery in July (as did fellow PuRPs Jordy Vargas and Gabriel Hughes), which ended his 2023 season and caused him to lose all of 2024 as well (he did pitch in fall instructs, just not an affiliated ball game).
When he was on the mound, Cox had some growing pains with a 10.32 ERA in four May starts and an 8.53 ERA in four June starts. On a positive note, Cox’s final two starts in July were both scoreless, as he struck out 14 hitters in seven innings while allowing five hits and two walks. In all, Cox threw 31 innings with a 7.26 ERA (5.37 xFIP), 1.90 WHIP, 9.3 K/9 rate, and 5.8 BB/9 rate.
Here’s some video of Cox from a prospect showcase in 2022 courtesy of the Prospect Pipeline:
Cox was listed as a prospect of note by Eric Longenhagen of Fangraphs earlier this month:
Cox, who signed for $1.85 million out of high school in 2022, was another of Colorado’s many TJ rehabbers in 2024. He has a great curveball, but his below-average fastball velocity (he was 92-94 again during instructs), movement, and vulnerable plane aren’t a great fit with that curve. He’s pitched just 31 affiliated innings and struggled with control during those.
Keith Law of the Athletic ranked Cox 18th in the system in February 2024:
[Cox] was the Rockies’ 2022 second-round pick, taking an over-slot bonus, with a plus curveball and above-average fastball at the time, as well as a clean delivery that had him online to the plate and should allow him to throw strikes.
With Cox, we really just have to wait and see what has happened to his stuff once he’s back (likely with Low-A Fresno to start out), since most of the positive scouting commentary is from nearly two years ago. If he still has that foundational breaking ball to build around and a strong fastball to pair with it (bigger if), he’s a worthy arm to follow through the system. I ranked Cox as a 40 FV player just off my list, but by mid-season we should have more clarity on whether that’s too low or too high.