Sterner underwent season-ending surgery this week, opening up a spot in the A's bullpen for an arm to make their case for 2027.
At times this season, right-hander Justin Sterner was one of the most important relief pitchers in the Athletics bullpen. In the middle of June, the 29-year-old held a 3.18 ERA with a 1.06 WHIP as the club hummed along to a 36-37 record. Since that point, the A's have gone just 11-37.
In that same span, Sterner has gone from one of the team's relied-upon pitchers, holding a 3.18 ERA in 34 innings, to the worst pitcher on the staff among pitchers with at least five innings. Since June 17, Sterner has held a 17.65 ERA (12.43 FIP) in 8 ⅔ innings.
Sterner landed on the IL back on July 18 with right knee chondromalacia, and on Thursday he underwent successful right knee surgery with Dr. Mike Banffy at the Cedars-Sinai Orthopedic Center in Los Angeles. Dr. Banffy performed a chondroplasty of the medial femoral condyle and a PRP injection.
Dr. Banffy is also the one who performed Shea Langeliers' right knee surgery and Mark Leiter Jr.'s right hip surgery last month. Leiter is out for the season, while there is a slim chance that Langeliers makes it back for a few games this season, likely as the A's DH.
Sterner is headed back to Sacramento on Friday to begin his rehabilitation, and will miss the rest of the 2026 season.
The right-hander's pitch mix has relied much less heavily on his four-seamer this season, going from 52.2% in 2025 to 39.5%. The big difference is that his sweeper has been getting used more often, up from 15.7% to 29.6%, essentially giving him three pitches that he can throw at any time.
Part of the reason for this has to be that Sterner's four-seamer has been slugged at a much higher rate, going from a .350 SLG last season to a .540 SLG this year. While the difference is stark, the difference in the expected stats is much less, a 61-point difference, rather than nearly 200.
The injury to Sterner has opened up a spot in the bullpen for the club to figure out who will be in their relief mix next season. Right now, Hogan Harris may be the only surefire reliever for the green and gold. Sterner, when healthy, figures to be used in some capacity as well.
How the A's end up attacking the offseason — particularly with bullpen additions — should give us a good idea of how the team plans to deploy Sterner in 2027.
