A native of Los Angeles, Lillis signed with Brooklyn in 1951 and appeared to be ready to replace Pee Wee Reese at shortstop in 1958, the year the Dodgers moved to Los Angeles. After injuries delayed his debut, he batted .391 in 20 games in 1958, but he lost the shortstop job to rookie Maury Wills in 1959. He was swapped to the Cardinals in mid-1961, drafted by the expansion Colt .45s that winter, and was the team’s MVP in its inaugural season. He batted a career-high .268 in 1964 and remained a Houston regular until 1966. A scout and instructor in the Astros organization from 1968 to 1972, he joined their major league coaching staff in 1973 and replaced Bill Virdon as manager on August 10, 1982. Leading the Astros to third place in 1983, Lillis finished second in NL Manager of the Year voting. After an 83-79 record in 1985, he was replaced by Hal Lanier.