Lemon spent his entire playing career in Cleveland with the Indians from 1941 to 1958. He spent five games on the roster as a third baseman in each of his first two years before missing three years due to military service during World War II.
When he returned, he was converted into a pitcher and he became a seven-time All-Star while winning 20 games or more seven different times. In all, he posted a 207-128 record in 460 games with 188 complete games and 31 shutouts. He led the league in strikeouts and shutouts once, games started and wins three times, innings pitched four times, and complete games five times.