Along with starting pitching, the Boston Red Sox's most significant need this winter has to be bullpen help.
After a strong first half in 2024, the Red Sox bullpen crumbled after the All-Star break, pitching to a paltry (and league-worst) 5.45 ERA. Overall, if Boston has any desire to contend for the postseason in 2025, Craig Breslow and Co. must seriously invest in relievers this winter.
Lucky for them, this year's free agency class boasts a lot of talent and postseason experience. In no particular order, here are the top five free-agent relievers for 2025.
5 free agent relievers the Red Sox should target for 2025
1. Tanner Scott
First on our list is Padres reliever Tanner Scott. Scott, an All-Star in 2024, pitched to a 1.75 ERA, a FIP of 2.92, and an ERA+ of 252 in 72 innings with the Marlins and Padres, accounting for a 1.6 fWAR. On top of his impressive regular season, Scott also posted great numbers in the playoffs, striking out eight while surrendering just two hits and two walks in 5.1 innings.
Scott would be a great acquisition for the Red Sox. In addition to his postseason experience, he could fill Boston's closer role, as he had 22 saves in 2024.
2. Jeff Hoffman
Another excellent option for the Red Sox bullpen is Jeff Hoffman. Also an All-Star in 2024, Hoffman pitched to a very successful season. In 66.1 innings of work for the Phillies, Hoffman posted a 2.17 ERA, a FIP of 2.52, and an ERA+ of 188. Hoffman also amassed a fWAR of 2.0, ranking him seventh among all qualified relievers.
3. Carlos Estévez
Coming in third on our list is Carlos Estévez. Estévez, also part of Philadelphia's elite bullpen, put together a strong resumè in 2025. In 55 innings with the Angels and Phillies, Estévez had a 2.45 ERA, a FIP of 3.24, and an ERA+ of 171. Additionally, contrary to the rest of the Phillies' pen, Estévez put up solid numbers in the postseason and let up just one run in his three appearances.
4. AJ Minter
AJ Minter would be another strong option for the Boston bullpen. Minter, who spent his 2024 in Atlanta, had some health issues, leading to season-ending hip surgery in August. However, despite his health issues, Minter put together a solid year.
In 34.1 innings, he finished 2024 with a 2.62 ERA, an FIP of 4.45, and an ERA+ of 160. While Minter's 4.45 FIP and fWAR of -0.1 may raise some alarm, they appear to be outliers, as throughout his career, Minter has posted a strong FIP of 2.89 and a fWAR of seven.
5. Chris Martin
Last but not least, Chris Martin would be another dependable option for the Red Sox bullpen, which they already know. Martin, who also dealt with injury in 2024, still put together a very successful campaign. Despite the bullpen's second-half collapse, in 44.1 innings, he posted a 3.45 ERA, an FIP of 2.78, and an ERA+ of 124. A valued member of Boston's bullpen, Martin also put up a solid 0.9 fWAR.
Overall, a deal with Martin makes sense with Boston, as he was one of the team's best pitchers in 2023 and 2024 and expressed interest in resigning for his final season in 2025.