Tigers Bring Back RJ Petit After Rockies Return Rule 5 Pick

The Detroit Tigers have another opportunity to develop a reliever they lost last winter. The Colorado Rockies returned right-hander RJ Petit to Detroit on Nov. 3, nearly 11 months after selecting him first overall in the 2025 Rule 5 draft.

Petit, 27, never reached the regular-season mound for Colorado. He made three spring training appearances before undergoing Tommy John surgery in March, ending his 2026 season and interrupting a promising stretch that had carried him through the upper levels of Detroit's system. His potential contribution in 2027 will depend on his recovery and how his pitches respond once he returns to competition.

The results before the injury explain the interest. Petit finished 2025 with a 2.44 ERA, 79 strikeouts and 22 walks in 66 1/3 innings between Double-A Erie and Triple-A Toledo. He made 47 appearances and continued producing after his promotion, recording a 2.74 ERA with 33 strikeouts in 23 innings for the Mud Hens.

At 6-foot-8, Petit presents an unusual look, but his appeal extends to the depth of his arsenal. Baseball America's Rule 5 scouting report identified a four-seam fastball, sinker, slider and changeup. The slider was his primary swing-and-miss offering, while the two fastballs gave him different movement profiles to use against hitters. Those preinjury tools give Detroit a foundation to evaluate during his return.

Petit also showed progress in an area that can determine whether a minor league reliever survives against major league hitters. His walk rate declined from 11.1% at Erie in 2024 to 8.2% across his two stops in 2025, according to FanGraphs. Limiting free baserunners would help him make better use of his ability to miss bats against stronger competition.

The return reflects the restrictions attached to the Rule 5 process. A selected player must spend at least 90 days on an active major league roster to clear that portion of the requirements, and time on the injured list does not count toward that minimum. Colorado would have carried those restrictions into another season had it retained Petit. Detroit's transaction record lists him assigned to Toledo.

Detroit has already begun reshaping its pitching staff, declining Kenley Jansen's option, reinstating Will Vest and signing Jacob Waguespack for 2027. Petit adds another possibility as that work continues, although his rehabilitation makes it premature to pencil him into a bullpen spot.

The Tigers can now evaluate whether Petit can recover the combination of strike throwing and missed bats that made him attractive to Colorado. If he does, his experience working beyond one inning could eventually give Detroit another option when a starter exits early or the bullpen needs coverage across several outs. The next useful evidence will come from his pitches and workload when he resumes game action.