The Chicago White Sox signed Aaron Bummer to a five-year, $16MM contract extension, tweets USA Today’s Bob Nightengale. The deal also includes two option years that could raise the overall value to $29.5MM, per Nightengale. Nightengale notes that it’s the “largest extension given to a non-closer who has yet to qualify for salary arbitration in #MLB history.” Bummer is represented by O’Connell Sports Management.
Bummer, 26, evolved into a reliable lefty out of the pen for the ChiSox last season, and he’s now set to burn worms on the Southside through the 2026 campaign. Bummer will make $1MM this season, $2MM in 2021, $2.5MM in 2022, $3.75MM in 2023, and $5.5MM in 2024. The option years are for $7.25MM and $7.5MM, respectively, with $1.25MM buyouts, per MLB.com’s Scott Merkin. The 2026 option could escalate to $9MM with a second- or third-place finish in the AL Reliever of the Year voting, or $10MM if he wins the award, according to The Athletic’s James Fegan.
The White Sox are getting one of the game’s premier groundball artists at rates that carry minimal risk. The investment signals both their confidence in Bummer, and their continued commitment to longevity for the incoming core. Bummer was among the best in the game at limiting barrels last season (2.3% barrel%) and well as opponents’ expected slugging percentage (.281 xSLG). Bummer’s sinker drives his arsenal, and it jumped in velocity last year to an average of 95.6 mph. In 58 games out of the pen last season, the southpaw produced a 72.1 GB%, ranking behind only the Yankees’ Zack Britton in that regard.
Big picture, Bummer joins Luis Robert and Eloy Jimenez as White Sox to have been extended through 2026 (including option years). The ChiSox now have a long-term piece in their bullpen to add some stability to that area of the club. In an era of flame-throwing strikeout artists, Bummer also brings a different approach. Should he continue to pitch as he did last season (2.13 ERA/3.41 FIP), the Sox will happily charge him with care of their late innings.