Season in Review: Justin Sterner's Roller Coaster Rookie Year with the A’s
Justin Sterner’s 2025 season was anything but predictable. The right-handed reliever went from relative unknown to Opening Day roster surprise, then from dominant bullpen weapon to a brief midseason demotion, and back again. For a rookie trying to carve out a role in a rebuilding bullpen, Sterner gave the Athletics more than they likely expected-and maybe even more than they realized they needed.
Let’s break down how Sterner got here, what he showed in his first full big league season, and why he’s squarely in the mix for a key role in 2026.
From Undrafted to Oakland: The Road Less Traveled
Sterner’s path to the majors wasn’t exactly lined with top prospect buzz or first-round expectations. After going undrafted during the shortened 2020 MLB Draft, he signed with the Miami Marlins as a free agent.
He was a starter in college, but the Marlins quickly shifted him to the bullpen, where his stuff had a better chance to play up. That move may have saved his career.
It didn’t take long for Sterner to be on the move again. After just half a season in Single-A, Miami traded him to the Tampa Bay Rays in exchange for David Hess. The Rays, known for their knack for finding hidden gems, kept him in their system, and Sterner climbed the ladder quickly-reaching Triple-A in just his second full pro season.
He finally got his first taste of the majors on May 31, 2024, with the Rays. But it was brief-just two appearances before he was sent back to Triple-A.
That could’ve been the end of the story, but the A’s saw something worth taking a shot on. On November 4, they claimed Sterner off waivers and added him to the 40-man roster.
That move, at the time, barely made a ripple. But it turned out to be one of the more quietly impactful decisions of the A’s offseason.
Low Expectations, High Impact
Coming into Spring Training, Sterner was viewed as depth-another arm in camp with a chance to eat innings if things broke right. He was 28, had just two MLB appearances to his name, and wasn’t on many radars.
But Sterner didn’t just show up-he dominated. In 12 innings of Cactus League work, he didn’t allow a single earned run and posted a 17-to-2 strikeout-to-walk ratio. That kind of spring forces coaches to take notice, and he earned his way onto the Opening Day roster.
Then came the real surprise: he kept it going.
Sterner opened the regular season with 18 consecutive scoreless outings, covering 18 2/3 innings. That stretch set a new mark for the longest scoreless streak by an A’s reliever to start a season since Jake Diekman in 2020.
He wasn’t just holding the line-he was setting the tone. Over that run, he struck out 24 and walked just nine, showing a mix of poise and power that made him one of the most reliable arms in the A’s bullpen.
The Rough Patch
But baseball has a way of humbling you, and Sterner’s inevitable regression came fast and loud.
Facing the Yankees, Sterner couldn’t record an out and gave up five earned runs in a single outing. Just like that, his ERA jumped from 0.00 to 2.33. He bounced back with six more scoreless appearances, but the damage had been done-not just statistically, but in terms of momentum.
By late May, the wheels started to wobble. A tough outing against Houston led to his first career loss, and it spiraled from there.
Over his next three appearances, he gave up runs, blew leads, and took losses. For a pitcher who had quickly earned trust, the sudden downturn was jarring.
The A’s made the call to send him down to Triple-A Las Vegas to regroup. He made three appearances there, giving up three runs in three innings. Not exactly a lights-out performance, but with Oakland’s bullpen in need of reinforcements, it was enough to earn a return ticket.
A Strong Finish
Sterner’s second stint with the A’s wasn’t flawless, but it was steady. July brought a few bumps-six earned runs over 12 innings-but once August hit, he started to look more like the pitcher from early in the season.
Over the final two months of the year, he allowed just four earned runs in 15 2/3 innings. He was especially sharp in September, giving up just one run all month. That late-season rebound helped him finish the year with a 3.18 ERA across a team-high 59 appearances.
For a rookie reliever claimed off waivers, that’s a win. For a team trying to build a bullpen from the ground up, it’s a potential building block.
Looking Ahead to 2026
The A’s are expected to be active in their search for bullpen help this offseason. That makes sense-depth and experience are still in short supply. But Sterner’s performance in 2025 puts him in a strong position heading into Spring Training.
He’s likely penciled in as a setup option for Mark Kotsay, and if the A’s don’t land a proven closer this winter, Sterner could even get a look in the ninth. He doesn’t have a track record of saves-just 15 in the minors and none in the majors-but he’s shown the ability to handle high-leverage spots when he’s on.
Ideally, Sterner slots in as a bridge to a more established closer. But if he ends up being the guy in the ninth, it wouldn’t be the worst-case scenario.
He’s earned the chance to prove he can be more than just a nice story. Now the question is: what can he do for an encore?
One thing’s clear-Justin Sterner came into 2025 as a long shot. He leaves it as a legit bullpen piece. And for a club still searching for answers, that’s a development worth betting on.