Larker played in the minor leagues even before 1950. He reached the majors in 1958 with the Dodgers –the first season that they played in Los Angeles–, spending four years with them before moving to the Houston Colt .45's (1962), Milwaukee Braves (1963), and San Francisco Giants (1963).
As a 27-year-old rookie, Larker hit .277 with a .427 slugging percentage in 99 games, mostly as an outfielder. He later became the regular first baseman for the Dodgers in replacement of Gil Hodges. His most productive season came in 1960, when he finished second in the National League batting race with a .323 average and was selected to the All-Star Game. As a member of the original Colt .45's in 1962, he collected career-highs in home runs (9), triples (5) and runs (58), while leading the team in doubles (19) and on base percentage (.358); tied for the team-lead in walks (70), and hit .263 on a team that posted a collective .246. average. He also was a member of the 1959 World Champion Dodgers and was considered in the 1960 National League MVP vote.
In a six-season career, Larker was a .275 hitter (538-for-1953) with 32 home runs and 271 RBI in 667 games, including 227 runs, 97 doubles, 15 triples, and three stolen bases. He also collected a .347 OBP and a solid 1.28 walk-to-strikeout ratio (211-to-165).
Larker died in Long Beach, California, at the age of 76.