McLish was born in Anadarko, Oklahoma, on December 1, 1925.[2] McLish's parents were John E. and Lula McLish.[3] His father is listed as "Choctaw by Blood" with a blood quantum of 1/8th on the Dawes Rolls.[4] He was the seventh of eight children. He was named for Calvin Coolidge, Julius Caesar, and Tuskahoma, Oklahoma.[5] He stated that the origin of his lengthy name is that his father was given permission to name the newborn, after not getting to name his previous six children,[why?] and he took full advantage of the opportunity.[5][6] He was raised in Oklahoma City, and went to its Central High School.[2]
McLish won 20 games for the Angels during the 1950 season. The Cubs sold McLish to the San Diego Padres, also in the PCL, in 1955. In 1956, McLish returned to MLB, pitching for the Cleveland Indians. He had a 16-8 win–loss record for Cleveland during the 1958 season, with a 2.99 earned run average (ERA).[5][11] In the 1958 and 1959 seasons, McLish set a major league record with 16 consecutive wins in road games. This was later surpassed by Greg Maddux.[2] In 1959, McLish had a 19–8 win–loss record with a 3.62 earned run average. He appeared in the 1959 MLB All-Star Game, earning the save for the American League.[2][5] Despite having a chance for his 20th win, Indians management asked McLish to forgo his final start of the season so that Herb Score could pitch, as he returned from injury.[12]
After the 1959 season, the Indians traded McLish with Gordy Coleman and Billy Martin to the Cincinnati Redlegs for Johnny Temple.[11] Disappointed by the trade, McLish said that Indians' general managerFrank Lane "never did like me".[13] McLish played for the Redlegs in 1960. After the season, they traded McLish and Juan Pizarro to the Chicago White Sox for Gene Freese.[14] Before the 1962 season, the White Sox sent McLish to the Philadelphia Phillies when Andy Carey, who they had traded to Philadelphia, refused to report. Carey instead went to the Dodgers, and McLish was sent to the Phillies.[15] In 1963, McLish had a 13–11 win–loss record in 211 innings pitched, the most on the team. He suffered from an injured shoulder the next season, and the Phillies released McLish in July 1964.[16]
After his playing career, McLish became a major league pitching coach for the Phillies, under Mauch, the Phillies' manager. He coached for the Phillies in 1965 and 1966, and then spent the next two years scouting for the Phillies.[17] He then followed Mauch to the expansion Montreal Expos in 1969,[18] where he served as pitching coach and developed pitchers Bill Stoneman, Carl Morton, Steve Renko, and Ernie McAnally.[7] He was ill in 1973 with bronchial pneumonia, and team doctors sent him home to recuperate.[19]
The Expos fired Mauch and McLish after the 1975 season. He was soon thereafter hired to coach the Milwaukee Brewers.[17] He coached the Brewers from 1976 through 1982.[2] He then served as a scout for the Brewers. He worked in professional baseball through 2005, when he was an instructor for the Seattle Mariners.[12]
McLish and his wife, Ruth, were married for 60 years. He had a daughter, three sons, and thirteen grandchildren. McLish died of leukemia at his home in Edmond, Oklahoma.[5]