I was driving to the grocery store yesterday with my brother, and during the drive, he turned and asked me, “Is Aaron Bummer actually good?”
I paused. I didn’t know what to say. If you scroll down to the bottom of the page and look at my bio, you will see that I am an avid Aaron Bummer fan – I’ve been a fan since he made his debut. He has an intriguing arm angle, his stuff is crazy, he strikes guys out, and he doesn’t let up homers. What’s not to like?
Being a fan of Bummer comes with some baggage, however. I’ve had to defend him on many occasions. Not a lot of people love Bummer as I do he is a “bummer” to a lot of fans. (I’m sorry, I had to make that joke). He has control issues. His walk rate is poor at best, and sometimes, those walks build up and turn into runs.
This year is no different. Bummer has had a bad start to this season. His walk rate is an abysmal 16.7%, and his ERA sits at 7.50. TO build on that, his WHIP is above 2. He is not playing well this year.
So, that begs the question: is Aaron Bummer good?
Was he ever good?
Yes. Aaron Bummer has always been a good pitcher.
Bummer’s career ERA is 3.15, and his career FIP is 3.34. In the past 4 seasons, his K/9 is above 10. To put these numbers into context, here are the leaders for the lowest HR/9 since 2019 (min. 160 IP).
| Relief Pitcher | HR/9 | ERA | FIP |
| 1. Emmanuel Clase | 0.41 | 1.55 | 2.31 |
| 2. Tyler Rogers | 0.43 | 2.82 | 3.21 |
| 3. Aaron Bummer | 0.49 | 2.77 | 2.15 |
Emmanuel Clase was All-MLB First Team, led the league in saves, and won Mariano Rivera AL Reliever of the Year last year. Tyler Rogers doesn’t have the same accolades as Clase but holds a career 2.82 ERA. Both of these guys are the closers for their team. They play at a high level, yet for some reason, everybody wants the third guy on the list DFA’ed.
Bummer also has some of the best stuff in the league, as evidenced by the vertical movement on both his sweeper and sinker.
When you stack him up against some of the best in the league, it’s clear that Aaron Bummer has been a good pitcher for the South Siders. As Sox fans, we started asking the same questions when Liam Hendriks struggled with a 5.40 ERA in April. Everybody freaked out, but in the end, he returned to form as he has done his whole career.
Aaron Bummer is no different. He struggles at times. He is struggling right now.
Is he good right now and will he get better?
No. There is no magical analytical stat that I can pull out to tell you that he has been a good pitcher this season.
Looking at Bummer’s ERA hurts the eyes, but his xERA is 1.19 points lower than his actual ERA. His SIERA (Skill Interactive ERA) is even less than that, sitting at 4.92. His FIP (Fielding Independent Pitching) is lower than that and sits at 3.98.
What is this meant to represent?
In a large part, it simply represents luck – both good and bad – for a pitcher. In Aaron Bummer’s case, he has been incredibly unlucky to start the season. A 3.98 FIP is still high, yes, and that comes from all the walks he surrenders. However, the BABIP against him is at an astronomical .412. League average BABIP is .300, so a .400+ BABIP tells us that when the ball leaves the bat, balls tend to land in play a lot more than other pitchers in the league. Over time, these hits will end up becoming outs, and his ERA will start to stabilize over time.
But what about the walk rate? Here is Bummer’s walk rate his whole career:
| Season | Innings Pitched | BB/9 | BB% |
| 2017 | 22.0 | 6.14 | 16.5% |
| 2018 | 31.2 | 2.84 | 6.9% |
| 2019 | 67.2 | 3.19 | 9.2% |
| 2020 | 9.1 | 4.82 | 13.2% |
| 2021 | 56.1 | 4.63 | 12.0% |
| 2022 | 26.2 | 3.38 | 8.5% |
| 2023 | 6.0 | 7.50 | 16.7% |
Looking at 2023, we can see his BB% hasn’t been this high in his whole career. He does usually have a high BB%, but it hasn’t been this bad. Historical trends say that he is likely to see his walk rate stabilize.
The Verdict
Watching Aaron Bummer give up the only hit for a combined no-hitter the other day was tough – a combined no-no would have been fun. However, Bummer’s early-season performance is just that: early-season. He is likely still working through things and getting into his rhythm, especially considering he had to miss some time this Spring Training due to an injury. He should not lose his spot because of a small sample size and some poor recent performances. When you take a look at the whole pitcher, Bummer has been one of the best pitchers in our bullpen and the league over the past five seasons, and it is highly likely he will bounce back to his normal self.
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Featured Image: Matt Marton-USA TODAY Sports
The question is not is Aaron Bummer good but is our pitching coach good. You often mention historical trends but what about those trends that account for managerial and pitching coach decisions that place a pitcher in out-of-norm situations, try this arm angle, release point, mound positioning, experiment pitch, inconsistent job description: mop up, innings eater, bridge, or occasional closer. I say this because the manager and coaches are under great pressure to try anything to win. I agree, Bummer, if left alone, will find his rhythm.
Very interesting point
Thank you.