Cubs Sign Aptly-Named Former White Sox RP Aaron Bummer to Minors Deal
The Cubs have been bailing water from a sinking ship all season when it comes to their pitching staff, and the latest bucket comes in the form of lefty Aaron Bummer. Like the addition of Bummer’s former White Sox teammate, Liam Hendriks, this move may have come a few years too late to be of much help. There was a time when I was clamoring for the Cubs to acquire the low-slot lefty for his ability to generate grounders at an incredible rate, but his performance has resembled his last name this season.
From 2020-24, Bummer posted a nearly 30% strikeout rate while keeping the ball on the ground 64.4% of the time. That latter mark was better than all but two of the 589 MLB pitchers with at least 100 innings in that span, and Bummer’s 76.1% clip in 2021 was the second-best season out of 2,527 pitchers with at least 20 innings in any one of those five campaigns.
After struggling with the Sox in 2023, Bummer was traded to the Braves for a package that included former Cubs greats Michael Soroka and Nicky Lopez. Bummer rebounded with Atlanta in 2024, but his strikeout rate dropped precipitously last season and has continued to do so this year. In just 15.1 innings over 19 appearances, Bummer has a 7.63 ERA with an 8.62 FIP. He has walked 10 batters with just 13 strikeouts, and six of the 18 hits allowed have gone for homers.
That home run total is as many as he’s allowed in any two consecutive seasons in the past, and he’s in the 1st percentile of MLB pitchers for average exit velocity (93.6 mph) and hard-hit rate (54.7%). Once more of a sinker/sweeper guy, Bummer has dialed both back significantly to incorporate more curveballs and four-seams. I’m not sure that’s the best idea when his hard stuff is sitting 90-91 after being 94-96 in his prime. And the curve has been his worst pitch by far, so I’m not really sure why it’s being used at all.
With all that in mind, you might be wondering why the Cubs signed him. But c’mon, is there anything Jed Hoyer loves more than soft-tossing relievers who are past the age of 30 and appear to be cooked? I dare say there is not. Bummer is not yet 33 and might benefit from a new pitching philosophy that sees him tweak his repertoire, but this doesn’t strike me as much more than a no-risk lottery ticket.
