Chicago Cubs Sign Veteran Pitcher With 3.94 Career ERA
Bummer was released by the Atlanta Braves on May 19 after posting a 7.63 ERA and an 8.62 FIP across 19 appearances and 15.1 innings, with a walk-to-strikeout ratio of 10 to 13 that showed a pitcher who could not consistently miss bats or locate his fastball.
He is expected to report to Triple-A Iowa.
The signing lands the Cubs their second former Chicago White Sox pitcher this month, following the Liam Hendriks minor league deal announced earlier in May.
Aaron Bummer agrees to Cubs deal @BNightengale 1st
— Jon Heyman (@JonHeyman) May 27, 2026
Bummer, 32, spent the first seven seasons of his career on the South Side before being traded to Atlanta as the centerpiece of a seven-player deal that also included Nicky Lopez, Michael Soroka, and three others.
He then signed a two-year deal with the Braves worth $12 million, which looked reasonable based on what he had produced in his first two Atlanta seasons.
From 2024 through 2025, Bummer posted a 3.69 ERA across 109.2 innings with a 56.8 percent ground-ball rate and career-good strikeout and walk numbers, establishing himself as one of the better setup options on a two-time World Series championship staff.
Then 2026 happened.
His fastball dropped from the mid-90s to 90 mph. His slider lost its bite, and the results followed.
The Chicago Cubs sign veteran reliever Aaron Bummer to a minor league contract after being recently released by Atlanta.
— Bob Nightengale (@BNightengale) May 27, 2026
A season-ending injury in August 2025 that he spent the offseason recovering from is the most commonly cited explanation for why a pitcher who was functional and reliable for two full seasons in Atlanta has been ineffective this year.
The Cubs have built one of the sport's better pitching development reputations under their current front office and believe the drop in velocity and movement can be at least partially addressed through mechanical adjustments.
They are presently dealing with six relievers on the injured list simultaneously and have been forced to construct their bullpen with reclamation projects and waiver wire pickups for the better part of two months.
At a minor league deal that costs essentially nothing if it fails, adding a 32-year-old lefty with 397 career innings and a track record of elite ground-ball generation and multi-inning reliability is a sensible bet regardless of what 2026 has looked like so far.
Photo Credit: Sam Navarro-Imagn Images
