Jimmie Foxx
While much of his production came during the first half of his career in Philadelphia, Jimmie Foxx remained a Beast during his time in Boston.
Foxx is 19th in MLB history with 534 home runs, 222 of which came during his time with the Red Sox to rank 9th on the franchise list.
An All-Star in all six of his full seasons in Boston, Foxx hit no fewer than 35 home runs during the first five years he spent wearing a Red Sox uniform. He hit only 19 in 1941 and was traded midway through the following season. His power production really fell off a cliff in his remaining few years due to injuries.
Foxx led the majors in home runs four times in his career, including once with the Red Sox. His best season in Boston was in 1938 when he clubbed 50 home runs and drove in a league-leading 175 RBI to earn his third career-MVP award. His 50-homer campaign stood as the Red Sox single-season record for nearly seven decades until it was finally broken by another slugger on this list (queue ominous foreshadowing music).
The .605 slugging percentage that Foxx produced during his time in Boston ranks second in franchise history. To put that in perspective, only four major league players produced a slugging percentage last season that topped what Foxx averaged in his time with the Red Sox. Foxx led the majors in SLG and OPS five times in his career, including twice in Boston.
His stint with the Red Sox was shorter than anyone else on this list but with his overall career numbers and outstanding individual seasons, we can’t put Double X any lower than third.