The White Sox announced this morning that they are agreeing to terms with the left-hander Sean Newcomb for the southpaw’s $4.5MM guaranteed one-year deal this morning. Will Samson of The Athletic reports that Newcomb “at least I’ll get the first chance” in Chicago. On the left Ryan Rolison was selected by assignment to replace Newcomb on the 40-man roster. Newcomb is a client of Tidal Sports Group.
Newcomb, 32, was a first-round pick by the Angels back in 2012 and spent years as a top-100 prospect in the minors. The lefty made his major league debut with Atlanta back in 2017 after coming on as part of the team’s Andrelton Simmons trade. He spent the first two seasons of his career as a replacement, with a 4.06 ERA (103 ERA+) and 4.16 FIP that gave him the look of a decent starter. Unfortunately, in 2019 early season struggles led to him being demoted to Triple-A and moved to a bullpen role upon his return. He started four games for the Braves in 2020 but struggled even where he started, and ended up not starting another game for the team before being assigned by the team.
The lefty was traded to the Cubs shortly after his DFA and moved into the team’s bullpen, but failed to put things together over the next few seasons. He pitched to a 6.61 ERA in 47 2/3 innings of work at the major league level between the Cubs and A’s over the next three seasons, with a staggering 15.0% walk rate. Back in January, Newcomb wrestled with the Red Sox on a minor league deal and found his way back into the major league rotation amid a strong performance in Spring Training coupled with injuries to rotation members such as Lucas Giolito again Brian Bello that kept them off the opening day roster.
Newcomb’s performance was once added to the rotation as a mixed bag. He made five starts for the Red Sox and posted a lackluster 4.43 ERA, but he did so with solid peripherals. He struck out 25.7% of his opponents while walking 10.5%. After moving to the bullpen, he posted a very strong 3.38 ERA in seven relief outings for Boston, though his strikeout rate dropped during those days. That led to the Red Sox designating him for assignment in late May, and he found himself traded back to the A’s shortly thereafter.
The left-hander stayed with the Athletics for the rest of the 2025 season and did very well for himself with the team. In a full-time relief role for the A’s, Newcomb has pitched to an impressive 1.75 ERA with a 2.69 FIP in 51 1/3 innings of work. That excellent play was backed up by strong peripherals, as he struck out 24.9% of his opponents, walked just 7.0%, and sent 48.9% of the hard ground ball. His 3.22 SIERA at West Sacramento would be good for 44th among pitchers with at least 50 innings last year when separated from his time in Boston. He would also rank fifth in ERA and 18th in FIP.
That performance is strong enough to justify giving Newcomb a solid one-year guarantee to be a bullpen left-hander, and the 32-year-old is likely to get the same dollar amount from a highly competitive team in 2026 based on the contracts given to comparable lefties this season. Caleb Thielbarwho also received steals with a $5MM guarantee earlier this month. That said, the contenders likely wanted to keep Newcomb in a full-time bullpen role. The White Sox, in contrast, have no prospects in contention heading into 2026 and therefore could offer Newcomb a chance to find a rotation spot this spring.
Fellow season signings Anthony Kay statistics to join Shane Smith again Davis Martin previously three replacements for the White Sox this year. That leaves Newcomb competing with the same players Sean Burke, Jonathan Cannonagain Chris Murphy of the last two places in the club rotation. It wouldn’t be a shock to see Newcomb fill that role, though it’s possible that he could be used in a more pinch-hitting role given that the Sox bullpen only has it. Mike Vasil again Jordan Leisure as options for getting help at the moment, with Tyler Gilbert as the top left option.
As for Rolison, the southpaw was claimed off waivers from Atlanta earlier this month. Rolison made his MLB debut as a member of the Rockies this past year, but struggled to the tune of a 7.02 ERA in 42 1/3 innings of work at the big league level in Colorado this year. The lefty will now be placed on the waiver wire again, unless the Sox make a deal involving Rolison before then. Should he go through waivers without being claimed, Rolison’s stats will be transferred to Triple-A as Chicago’s undrafted depth through the 2026 season.
