What happened: Boston acquired left-hander Jake Bennett from Washington in a mid-December prospect swap for right-hander Luis Perales. Bennett answered injuries in the Boston rotation with 113.1 innings after a 1.60 ERA in nine Triple-A starts. Perales countered with a 3.64 ERA innings at Rochester but walked over 13% of minor-league hitters.

Why it matters: Bennett posted a 3.65 ERA with 91 strikeouts to 21 walks and steadied Boston during Garrett Crochet's absence. Washington bet on Perales averaging 99 mph with a cutter and splitter, but command gaps muted that stuff advantage. Boston even dealt the more touted Connelly Early for offense after Bennett locked in as a mid-rotation arm.

What to watch: Watch whether Perales trims the walk rate enough for the velocity to play in Washington. Watch whether Bennett holds the mid-rotation role after a 4.66 ERA over his last seven outings.