Tuesday at 6 p.m. is the deadline for teams to protect Rule 5 eligible players by adding them to the 40-man roster.
The Red Sox have just one prospect, right-hander David Sandlin, who’s considered a lock to be protected.
There are a number of other prospects who are borderline.
Any eligible player who is left unprotected is available to teams in the December Rule 5 Draft.
Candidates to be protected:
David Sandlin, RHP: The hard-throwing 24-year-old is expected to be added to the 40-man roster.
Sandlin, whose fastball reaches triple digits, pitched well for Double-A Portland in 2025 in a starter/piggyback role. He posted a 3.61 ERA and held opponents to a .227 batting average in 17 outings (13 starts). But he struggled when he got moved to the bullpen after his promotion to Triple-A Worcester in late July. He posted a 7.61 ERA (23 ⅔ innings, 20 earned runs) in 15 outings (one start) for the WooSox.
Overall, he wasn’t as overpowering this season. His strikeout percentage dropped from 33.2% in 2024 to 23.4% in 2025.
The Red Sox acquired him from the Royals for right-handed reliever John Schreiber on Feb. 17, 2024.
MLB Pipeline ranks him the Red Sox’ No. 10 prospect. SoxProspects.com ranks him No. 13.
Shane Drohan, LHP: This is the third straight offseason that Drohan is Rule 5 Draft eligible.
The White Sox selected him in the 2023 Rule 5 Draft but they returned him to Boston on June 12, 2024, after he underwent shoulder surgery almost four months earlier.
He went unselected in the 2024 Rule 5 Draft after he pitched just 16 ⅓ innings that season following surgery.
But teams should be interested this offseason if the Red Sox don’t protect him today.
He missed from July 9 to August 26 with left forearm inflammation in 2025. But he pitched well when he was healthy, posting a 2.27 ERA and 1.01 WHIP while holding opponents to a .185 batting average in 12 outings (11 starts) for the WooSox.
Drohan posted a 35.2% strikeout percentage at Triple A using a swing-and-miss fastball, cutter, changeup, slider and curveball. His strikeout rate was well above his minor league career mark (26.3%).
Yordanny Monegro, RHP: The 23-year-old Dominican pitcher underwent Tommy John surgery after tearing his ulnar collateral ligament in June.
He’s likely to miss most of, if not all of the 2026 season. But a team still might select him if the Red Sox decide to leave him unprotected. If he misses the entire ‘26 season, the same Rule 5 requirements would apply to 2027.
For example, the Blue Jays selected injured Angel Bastardo in the 2024 Rule 5 Draft from Boston after his ‘24 was shortened due to Tommy John surgery. The Jays placed Bastardo on the 60-day IL for the entire 2025 season. He must remain on Toronto’s active roster for the full season in 2026 (barring an IL stint) or be returned to the Red Sox.
Monegro, a 6-foot-4 righty, has a 3.22 ERA, .221 batting average and a 29.9% strikeout percentage in 63 minor league outings (57 starts). He had a 2.67 ERA nine outings (eight starts) in 2025 before getting injured.
Jedixson Paez, RHP: The 21-year-old Venezuelan is an interesting name to watch.
He has pitched well in the minor leagues with a 3.22 ERA in 73 outings (58 starts). He’s known for his strong command and control, allowing just 1.4 walks per nine innings and posting a 3.9% walk percentage in the minors
Fangraphs’ ranks him Boston’s No. 13 prospect while SoxProspects.com has him at No. 17 and MLB Pipeline No. 20.
He missed much of ‘25 because of a calf injury. He made just seven starts for High-A Greenville and posted a 2.79 ERA while holding opponents to a .228 batting average.
He’s talented but he has never pitched above High A. Therefore, no team might be able to keep him on its active roster for a full season in 2026 because he still has a lot of development remaining.
Hayden Mullins, LHP: The lefty, who turned 25 in September, went 8-2 with a 2.21 ERA and 1.11 WHIP while holding opponents to a .177 batting average in 22 outings (21 starts) between High-A Greenville and Double-A Portland in 2025. He had a 2.44 ERA and held opponents to a .175 batting average in his 18 starts for Portland.
The 2022 12th-round pick out of Auburn struck out 30% of the batters he faced but he needs to improve his control (12.4%) walk percentage.
He throws a fastball in the 92-95 mph range. He also has two sliders and a changeup.
Tyler Uberstine, RHP: The 26-year-old is Rule 5 Draft eligible this offseason after a breakout season in 2025.
His strong year came after he missed the entire 2023 season and most of 2024 after undergoing Tommy John surgery.
The 2021 Red Sox 19th-round draft pick posted a 3.58 ERA in 25 outings (21 starts) for Portland and Worcester combined. Nineteen of those outings came with Worcester.
He throws a mid-90s fastball, a new cutter that he added during his Tommy John surgery rehab, a sweeper and a changeup.
Uberstine was not recruited out of high school after pitching just seven innings as a senior. He initially enrolled at USC as a regular student/non-athlete and studied business. But he hit a growth spurt between his freshman and sophomore year of college. He tried to walk on to the USC baseball team his sophomore year but didn’t make it. He eventually transferred to Northwestern where he earned a spot in their starting rotation his first year there in 2020.
Allan Castro: The 22-year-old batted .268 with a .353 on- base percentage, .400 slugging percentage, .753 OPS, seven home runs, 20 doubles, two triples, 37 RBIs and 43 runs in 92 games for Portland. He was successful on 15-for-18 stolen base attempts.
MLB Pipeline ranks him Boston’s No. 22 prospect while SoxProspects.com has him No. 26.
Miguel Bleis, OF: Baseball America ranked the 21-year-old outfielder Boston’s No. 5 overall prospect entering both 2023 and 2024. But he has struggled offensively since undergoing surgery in June 2023 for a left shoulder subluxation.
Baseball America won’t publish updated rankings until later this offseason but MLB Pipeline ranks him No. 15 in the Red Sox system while SoxProspects.com has him at No. 18.
He batted only .222 with a .300 on-base percentage, .385 slugging percentage and .685 OPS in 107 games between High-A Greenville and Double-A Portland in 2025, including a .209/.263/.291/.554 line in 30 games for Portland.
Two others of note: Righty Luis Guerrero, who Boston recently designated for assignment and outrighted to Worcester, is Rule 5 Draft eligible. So is 22-year-old lefty Eduardo Rivera who Boston recently re-signed to a minor league contract after he posted a 2.48 ERA in 20 outings (15 starts) for Greenville and Portland in ’25.
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