The Chicago Cubs bullpen should look and feel very different in 2025 than it was in 2024.
The 2024 season saw Jed Hoyer continue his approach of trying to combine rejects from previous organizations and turn them into high-leverage relief pitchers. That is not to take aim at the Cubs pitching infrastructure as it remains one of the best in all of Major League Baseball. That is moreso meant to take aim at the idea of always depending on reclamation projects to be the answer for a bullpen.
Of course, there were circumstances in 2024 the Cubs couldn't have predicted. Adbert Alzolay was broken from the start of the season, Hector Neris' regression advanced far past what the signs indicated during his final season with the Houston Astros, and Julian Merryweather was never quite healthy.
Given those lessons learned, it is comforting that Hoyer took a more aggressive approach to filling out the bullpen for the 2025 season. The additions of Eli Morgan, Ryan Pressly, and Ryan Brasier should provide the Cubs with much more stability in their bullpen than what they've had in recent seasons. Stability that will allow the Cubs to survive a potential sophomore slump from Porter Hodge
There is one addition that Cubs fans may not be talking enough about.
Lost in the shuffle of the reorganized bullpen is the Cubs' addition of veteran left-handed relief pitcher Caleb Thielbar to the mix on a one-year deal. One of the reasons why Thielbar's addition may be overlooked by Cubs fans is because he struggled with the Minnesota Twins last season. The 2024 season was the worst of his career, posting a 5.32 ERA in 59 appearances.
What Cubs fans may not know is the 2024 season for Thielbar was the exception to what otherwise has been a respectable career in Major League Baseball. Prior to 2024, Thielbar had three consecutive seasons of posting an ERA under 3.50. It's also the reason FanGraphs has Thielbar as one of the pitchers expected to bounce back in 2025. In looking at ERA+, where 100 is mean and any number higher than that is good Thielbar is projected to have an ERA+ of 103 in 2025. Such a mark would be up 92% from where he finished during the 2024 season.
If nothing else, Thielbar should be better in 2025. But, specifically, for the Cubs, his value could come in getting left-handed hitters out. Despite his struggles last season, Thielbar remained effective against left-handed hitters. Lefties slashed .244/.320/.333 against Thielbar last season, with the veteran southpaw also posting a 2.59 FIP against his lefty counterparts.