The White Sox are adding a familiar name to their pitching mix, agreeing to a one-year, $4.5 million deal with left-hander Sean Newcomb. The 32-year-old southpaw, once a top prospect and first-round pick by the Angels back in 2012, is getting another shot to prove he can stick in a big league rotation. According to reports, Newcomb will at least be given the opportunity to compete for a starting role in Chicago this spring.
To make room on the 40-man roster, the White Sox designated fellow left-hander Ryan Rolison for assignment.
Newcomb’s journey through the majors has been anything but linear. After debuting with the Braves in 2017-part of the return in the Andrelton Simmons trade-he looked the part of a solid back-end starter early on.
In his first two seasons, he posted a 4.06 ERA and a 4.16 FIP, numbers that suggested he could hold his own in a rotation. But inconsistency crept in.
By 2019, early struggles led to a demotion to Triple-A, and when he returned, it was in a bullpen role. He made a few more starts in 2020, but the results weren’t there, and Atlanta eventually designated him for assignment.
That led to a stint with the Cubs, where Newcomb was used exclusively out of the bullpen. Unfortunately, the command issues that had plagued him in Atlanta followed him to Chicago-and later to Oakland. Over parts of three seasons with the Cubs and A’s, he posted a rough 6.61 ERA in 47 2/3 innings, with a sky-high 15.0% walk rate that made it tough to trust him in any high-leverage spots.
But in 2025, Newcomb found a new opportunity-and a bit of a resurgence. He signed a minor league deal with the Red Sox, and a strong spring, combined with injuries to key rotation arms like Lucas Giolito and Brayan Bello, opened the door.
Newcomb was added to the Opening Day roster and made five starts for Boston. The 4.43 ERA didn’t jump off the page, but the underlying numbers told a more encouraging story: a 25.7% strikeout rate and a manageable 10.5% walk rate hinted at a pitcher who might still have something left in the tank.
After moving to the bullpen, Newcomb looked more comfortable. In seven relief outings for the Red Sox, he posted a 3.38 ERA, though the strikeouts dipped. Still, Boston designated him for assignment in late May, and he was soon traded back to the A’s.
That’s where things really clicked.
In a full-time relief role with Oakland, Newcomb was lights-out. He tossed 51 1/3 innings with a sparkling 1.75 ERA and a 2.69 FIP.
The peripherals backed it up: 24.9% strikeout rate, just 7.0% walks, and a strong 48.9% ground ball rate. His 3.22 SIERA would’ve ranked 44th among all relievers with 50+ innings last year-had those numbers stood on their own.
He’d also have placed fifth in ERA and 18th in FIP.
That kind of production made Newcomb an appealing free agent option this winter, and it’s easy to imagine a contending team offering him a similar deal-likely as a bullpen arm only. But the White Sox, not expected to contend in 2026, can afford to be more flexible. For them, Newcomb represents both a potential rotation piece and a high-leverage bullpen option if the rotation doesn’t pan out.
Right now, the White Sox rotation picture is still coming into focus. Anthony Kay, Shane Smith, and Davis Martin are the early favorites for the top three spots.
That leaves Newcomb in a spring battle with Sean Burke, Jonathan Cannon, and Chris Murphy for the final two rotation jobs. And if he doesn’t win a starting role?
The bullpen could use the help. Outside of Mike Vasil and Jordan Leasure, there aren’t many proven leverage arms, and Tyler Gilbert is currently the top lefty in the pen.
As for Rolison, his time on the White Sox roster may be short-lived. Claimed off waivers from Atlanta earlier this month, the lefty made his MLB debut with the Rockies in 2025 but struggled with a 7.02 ERA over 42 1/3 innings.
He’ll now hit waivers again unless Chicago finds a trade partner. If unclaimed, he’s likely headed to Triple-A as depth.
For Newcomb, this deal is about opportunity. After bouncing between roles and teams over the past few years, he’s got a real shot to earn a meaningful role in Chicago-whether it’s as a starter, a multi-inning weapon, or a late-inning lefty. And for a White Sox team still figuring out its identity heading into 2026, that kind of versatility is exactly what they need.