The Athletics acquired Newcomb from the Red Sox on Tuesday in exchange for cash considerations.
The left-hander was designated for assignment by Boston over the weekend, but he found a new home on an MLB roster. Newcomb opened the season in the Red Sox's rotation before shifting to a long-relief role, and overall he had a 3.95 ERA, 1.76 WHIP and 41:17 K:BB across 41 innings. The 31-year-old spent the 2023 and 2024 campaigns with the Athletics but pitched in just 14 games (two starts).