The Red Sox informed Watson on Monday that he will be included on the Opening Day roster, Chris Cotillo of MassLive.com reports.
The 28-year-old righty won a spot in the Boston bullpen after submitting a 5.56 ERA, 1.32 WHIP and 7:3 K:BB over 11.1 innings during the Grapefruit League. A Rule 5 Draft selection over the winter, Watson will need to be stashed on the major-league roster throughout the 2026 season, or else the Red Sox will have to offer him back to the Giants.