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Aaron Bummer
P
KC
2026 season
- GP
- 21
- W-L
- 1-2
- ERA
- 10.26
- WHIP
- 2.10
- K
- 13
- IP
- 16.2
Game log
| Date | Opp | Result | Dec | IP | H | ER | BB | K |
|---|---|---|---|---|---|---|---|---|
| Aug 6 | vs MIN | L 3-4 | L | 0.1 | 2 | 3 | 1 | 0 |
| Aug 2 | @COL | L 1-8 | - | 1.0 | 4 | 3 | 0 | 0 |
| May 18 | @MIA | L 0-12 | - | 1.0 | 3 | 6 | 5 | 1 |
| May 14 | vs CHC | L 0-2 | - | 1.1 | 0 | 0 | 0 | 1 |
| May 8 | @LAD | L 1-3 | - | 1.0 | 0 | 0 | 0 | 0 |
| May 4 | @SEA | L 4-5 | - | 0.2 | 2 | 0 | 1 | 1 |
| May 3 | @COL | W 11-6 | W | 1.0 | 3 | 2 | 0 | 2 |
| Apr 30 | vs DET | L 2-5 | - | 0.2 | 0 | 0 | 1 | 1 |
| Apr 28 | vs DET | W 5-2 | - | 1.0 | 2 | 2 | 0 | 0 |
| Apr 26 | vs PHI | W 6-2 | - | 1.0 | 1 | 0 | 0 | 1 |
| Apr 24 | vs PHI | W 5-3 | - | 1.0 | 1 | 0 | 0 | 0 |
| Apr 21 | @WSH | L 4-11 | - | 1.0 | 0 | 0 | 0 | 1 |
| Apr 20 | @WSH | W 9-4 | - | 0.1 | 0 | 0 | 0 | 0 |
| Apr 19 | @PHI | W 4-2 | - | 0.1 | 1 | 0 | 0 | 0 |
| Apr 13 | vs MIA | L 4-10 | L | 1.0 | 4 | 3 | 0 | 2 |
| Apr 11 | vs CLE | L 0-6 | - | 0.2 | 0 | 0 | 2 | 0 |
| Apr 10 | vs CLE | W 11-5 | - | 0.1 | 0 | 0 | 0 | 0 |
| Apr 7 | @LAA | W 7-2 | - | 0.1 | 0 | 0 | 1 | 0 |
| Apr 6 | @LAA | L 2-6 | - | 1.0 | 0 | 0 | 0 | 1 |
| Mar 30 | vs ATH | W 4-0 | - | 1.0 | 1 | 0 | 0 | 2 |
| Mar 28 | vs KC | W 6-2 | - | 0.2 | 0 | 0 | 0 | 0 |
| 2025 season | ||||||||
| Aug 23 | vs NYM | L 2-9 | - | 1.1 | 0 | 0 | 0 | 0 |
| Aug 17 | @CLE | W 5-4 | W | 2.0 | 1 | 0 | 0 | 1 |
| Aug 13 | @NYM | W 11-6 | W | 2.1 | 2 | 0 | 1 | 3 |
| Aug 9 | vs MIA | W 8-6 | - | 1.2 | 2 | 1 | 0 | 1 |
| Aug 6 | vs MIL | L 4-5 | - | 2.1 | 2 | 0 | 0 | 1 |
| Aug 4 | vs MIL | L 1-3 | - | 1.2 | 0 | 0 | 0 | 1 |
| Jul 29 | @KC | L 6-9 | - | 0.2 | 2 | 2 | 1 | 1 |
| Jul 25 | @TEX | L 3-8 | - | 0.2 | 1 | 0 | 1 | 0 |
| Jul 23 | vs SF | L 3-9 | - | 0.2 | 1 | 0 | 0 | 0 |
| Jul 21 | vs SF | W 9-5 | - | 1.0 | 1 | 0 | 0 | 0 |
| Jul 18 | vs NYY | W 7-3 | - | 0.2 | 3 | 3 | 0 | 1 |
| Jul 12 | @STL | W 7-6 | - | 2.0 | 4 | 3 | 0 | 1 |
| Jul 10 | @ATH | L 4-5 | L | 0.1 | 1 | 0 | 1 | 1 |
| Jul 5 | vs BAL | L 6-9 | - | 2.1 | 2 | 3 | 1 | 5 |
| Jul 2 | vs LAA | W 8-3 | W | 2.1 | 0 | 0 | 0 | 3 |
| Jun 25 | @NYM | L 3-7 | - | 2.2 | 3 | 0 | 0 | 2 |
| Jun 20 | @MIA | L 2-6 | - | 1.1 | 1 | 2 | 3 | 0 |
| Jun 15 | vs COL | L 1-10 | - | 0.2 | 1 | 0 | 0 | 0 |
| Jun 13 | vs COL | W 12-4 | - | 0.2 | 2 | 0 | 0 | 0 |
| Jun 10 | @MIL | L 1-4 | - | 0.2 | 1 | 1 | 1 | 0 |
| Jun 5 | vs AZ | L 10-11 | - | 1.2 | 1 | 0 | 0 | 1 |
| Jun 4 | vs AZ | L 1-2 | - | 0.1 | 0 | 0 | 0 | 0 |
| Jun 1 | vs BOS | L 1-3 | - | 2.0 | 1 | 0 | 0 | 5 |
| May 29 | @PHI | L 4-5 | - | 1.1 | 0 | 0 | 0 | 2 |
| May 22 | @WSH | L 7-8 | - | 1.1 | 1 | 0 | 0 | 2 |
| May 20 | @WSH | L 3-5 | - | 1.2 | 0 | 0 | 1 | 0 |
| May 17 | @BOS | L 6-7 | - | 0.1 | 2 | 2 | 0 | 0 |
| May 14 | vs WSH | L 4-5 | - | 0.2 | 3 | 0 | 0 | 0 |
| May 11 | @PIT | L 3-4 | - | 1.0 | 0 | 0 | 1 | 0 |
| May 9 | @PIT | L 2-3 | - | 1.0 | 0 | 0 | 0 | 2 |
| May 7 | vs CIN | L 3-4 | - | 1.2 | 0 | 0 | 1 | 2 |
| May 3 | vs LAD | L 3-10 | - | 2.0 | 3 | 0 | 0 | 2 |
| Apr 27 | @AZ | L 4-6 | - | 0.2 | 2 | 2 | 1 | 0 |
| Apr 25 | @AZ | W 8-2 | - | 1.0 | 0 | 0 | 0 | 1 |
| Apr 22 | vs STL | L 4-10 | - | 2.0 | 0 | 0 | 0 | 3 |
| Apr 18 | vs MIN | W 6-4 | - | 1.1 | 0 | 0 | 0 | 1 |
| Apr 14 | @TOR | W 8-4 | - | 1.1 | 3 | 1 | 0 | 2 |
| Apr 10 | vs PHI | W 4-2 | - | 1.0 | 0 | 0 | 2 | 1 |
| Apr 9 | vs PHI | L 3-4 | - | 1.1 | 1 | 1 | 0 | 2 |
| Apr 4 | vs MIA | W 10-0 | - | 1.0 | 2 | 0 | 0 | 2 |
| Mar 29 | @SD | L 0-1 | L | 0.2 | 1 | 1 | 1 | 2 |
| Mar 27 | @SD | L 4-7 | - | 1.0 | 1 | 1 | 1 | 0 |
| 2024 season | ||||||||
| Sep 30 | vs NYM | L 7-8 | - | 0.2 | 0 | 0 | 1 | 1 |
| Sep 22 | @MIA | W 5-4 | - | 0.1 | 2 | 0 | 0 | 1 |
| Sep 18 | @CIN | W 7-1 | - | 1.0 | 0 | 0 | 1 | 0 |
| Sep 16 | vs LAD | L 0-9 | - | 0.2 | 2 | 3 | 0 | 0 |
| Sep 14 | vs LAD | W 10-1 | - | 1.0 | 1 | 0 | 0 | 1 |
| Sep 11 | @WSH | L 1-5 | - | 0.1 | 0 | 0 | 0 | 1 |
| Sep 9 | vs CIN | L 0-1 | - | 1.0 | 0 | 0 | 0 | 2 |
| Sep 7 | vs TOR | L 5-9 | - | 1.0 | 0 | 0 | 0 | 1 |
| Sep 5 | vs COL | L 1-3 | - | 1.1 | 1 | 0 | 1 | 3 |
| Sep 1 | @PHI | L 2-3 | L | 0.2 | 0 | 0 | 1 | 0 |
| Aug 29 | @PHI | L 4-5 | - | 0.2 | 0 | 1 | 1 | 0 |
| Aug 25 | vs WSH | L 1-5 | - | 1.2 | 1 | 0 | 0 | 1 |
| Aug 24 | vs WSH | W 4-2 | W | 0.1 | 0 | 0 | 0 | 1 |
| Aug 15 | @SF | L 0-6 | - | 1.1 | 1 | 0 | 0 | 3 |
| Aug 10 | @COL | W 11-8 | - | 0.2 | 4 | 3 | 0 | 1 |
| Aug 7 | vs MIL | L 5-8 | - | 1.0 | 1 | 0 | 0 | 3 |
| Aug 6 | vs MIL | L 0-10 | - | 1.1 | 0 | 0 | 1 | 1 |
| Aug 4 | vs MIA | L 0-7 | - | 1.0 | 3 | 1 | 0 | 0 |
| Aug 2 | vs MIA | W 5-3 | W | 1.0 | 1 | 0 | 0 | 2 |
| Jul 29 | @MIL | L 3-8 | - | 1.0 | 2 | 1 | 1 | 1 |
| Jul 26 | @NYM | L 4-8 | - | 2.0 | 1 | 0 | 0 | 3 |
| Jul 22 | vs CIN | L 1-4 | - | 2.0 | 1 | 0 | 0 | 3 |
| Jul 20 | vs STL | L 5-9 | - | 1.0 | 2 | 0 | 0 | 3 |
| Jul 13 | @SD | L 0-4 | - | 1.0 | 0 | 0 | 0 | 3 |
| Jul 7 | vs PHI | W 6-0 | - | 1.0 | 2 | 0 | 0 | 0 |
| Jul 4 | vs SF | L 2-4 | - | 1.0 | 0 | 0 | 0 | 1 |
| Jul 2 | vs SF | L 3-5 | - | 0.1 | 2 | 1 | 0 | 0 |
| Jun 30 | vs PIT | L 2-4 | - | 1.0 | 0 | 0 | 0 | 1 |
| Jun 28 | vs PIT | W 6-1 | - | 1.0 | 2 | 1 | 0 | 3 |
| Jun 24 | @STL | L 3-4 | - | 1.1 | 2 | 0 | 0 | 1 |
| Jun 22 | @NYY | L 3-8 | - | 0.1 | 2 | 2 | 3 | 0 |
| Jun 19 | vs DET | W 7-0 | - | 2.0 | 1 | 0 | 0 | 2 |
| Jun 15 | vs TB | W 9-2 | - | 1.0 | 0 | 0 | 1 | 3 |
| Jun 12 | @BAL | L 2-4 | - | 0.1 | 0 | 0 | 0 | 0 |
| Jun 9 | @WSH | L 5-8 | - | 0.2 | 3 | 1 | 1 | 1 |
| Jun 6 | @WSH | W 5-2 | W | 1.0 | 0 | 0 | 0 | 1 |
| Jun 1 | vs ATH | L 9-11 | - | 1.0 | 1 | 0 | 0 | 1 |
Latest news
The Royals optioned Bummer to Triple-A Omaha on Friday, and Bummer elected to become a free agent.
The veteran left-hander had his contract selected last weekend, and he pitched in two games out of the bullpen for Kansas City. Bummer faced 11 batters but recorded just four outs, allowing six runs on six hits and one walk with no strikeouts. He'll try to find work elsewhere rather than heading to Omaha.
RotoWire via ESPN · Aug 7
The Royals selected Bummer's contract from Triple-A Omaha on Sunday.
The left-hander joined Kansas City on a minor-league deal July 20 and will get a look in the majors after delivering four scoreless outings for Omaha. Bummer made 19 appearances for Atlanta earlier this year and surrendered 13 earned runs with a 13:10 K:BB over 15.1 innings.
RotoWire via ESPN · Aug 2
The Royals signed Bummer to a minor-league contract Monday, Jon Heyman of the New York Post reports.
Bummer held a 7.63 ERA in 19 appearances for Atlanta earlier this season and has permitted four runs with a 6:2 K:BB over six innings during his time in the minors in 2026. The lefty reliever had a 26.9 percent strikeout rate in his first eight major-league seasons, but his strikeouts and velocity have both been down the last two years.
RotoWire via ESPN · Jul 20
Bummer opted out of his minor-league contract with the Cubs on Friday, Jon Heyman of the New York Post reports.
After being released by Atlanta in May following a 7.63 ERA in 19 appearances, Bummer allowed four runs with a 3:2 K:BB over four innings with Triple-A Iowa. The southpaw has the ability to negotiate with other teams, though it's possible he already has a deal in place somewhere.
RotoWire via ESPN · Jul 17
The Cubs signed Bummer to a minor-league contract Wednesday, Bob Nightengale of USA Today reports.
Bummer was released by Atlanta last week after collecting a 7.63 ERA and 1.83 WHIP across his first 19 relief appearances this season. The lefty's velocity has been tumbling in the wrong direction in recent years, but the Cubs will stick him at Triple-A Iowa and see if they're able to coax more out of the 10-year veteran.
RotoWire via ESPN · May 27
Atlanta released Bummer on Tuesday.
Bummer was torched for six runs on three hits and five walks over one inning of work in Monday's loss to the Marlins, pushing his ERA and WHIP on the season to 7.63 and 1.83, respectively. The veteran lefty's velocity has trended in the wrong direction in recent years, as the 90.2 mph he's averaging on his sinker is more than five mph lower than the 95.4 mph he averaged back in 2021. Bummer's track record should still be enough to land him a fresh start in a new organization.
RotoWire via ESPN · May 19