The Houston Astros didn’t have much space on the 40-man roster when the Rule 5 draft deadline came around. So, they had to prioritize.
The move Houston made was to put a top pitching prospect, Miguel Ullola on the 40-man roster. He has a chance to be a starter in 2026 and exposing him to the Rule 5 process likely would have led to him being selected. Keeping him was a no-brainer.
That meant leaving another pitching prospect unprotected, one that Baseball America (subscription required) listed among the Top 35 players that could be taken in the Rule 5 draft at next week’s MLB winter meetings — Alimber Santa.
Why Astros Are Hoping Everyone Passes on Alimber Santa
Santa is a Top 30 prospect in the Astros’ system, ranked No. 13 by MLB Pipeline. Houston has cultivated a potential MLB reliever in Santa, a 23-year-old native of the Dominican Republic who signed with the Astors as an international free agent in 2020. He’s eligible for the Rule 5 draft because he signed a contract before his 18th birthday and has played five minor league seasons.
Had Santa been eligible in 2024 losing him probably wouldn’t be an issue. He went 1-2 with a 6.47 ERA in 19 games with three different Astros affiliates. He struck out 49 and walked 23 in 40.1 innings. But, in 2025, he had a breakthrough, one good enough to catch everyone’s attention.
Houston left him unprotected as he was coming off a career-best season as a reliever. He went 3-2 with a 2.31 ERA in 2025. He had six holds and two saves in four chances. He struck out 82 and walked 39 in 70 innings as batters hit .185 against him. He pitched half of the season at Triple-A Sugar Land, and his ERA did swell to 6.92 in 15 games. He struck out 19 and walked 16 in 13 games. Prospective teams will have to determine if that’s just a player making a move to a higher affiliate or a sign of a regression.
“It’s a deep pitch mix with feel for spin and the ability to move the ball around the zone with a variety of different shapes,” per Baseball America’s staff.
The site recommended that Santa be selected as a low-leverage relief option to start. That recommendation is driven in part by what a team must do to select Santa.
A prospective suitor for Santa must have an open spot on the 40-man roster. If he’s selected, that team must roster Santa on the 40-man immediately and pay the Astros $100,000. Santa must remain on the MLB roster the entire season but can be moved to the IL for legitimate injuries. If Santa isn’t kept, he must be put on waivers, and any team can pick him up — but must assume the Rule 5 responsibilities. If he clears waivers, he must be offered back to the Astros for $50,000. If the Astros don’t want him, then Santa becomes a free agent.
Houston is gambling that teams that have 40-man spots won’t want to go to the trouble of selecting him.
