Klein's professional career began as a shortstop at age 21 in the Cardinals' farm system. He rose from Class D, the lowest level, in 1940 all the way to the top-level Columbus Red Birds in 1941, and needed only three years of minor league seasoning to reach the big leagues. In his rookie season in the Majors, with the reigning world champion 1943 Cardinals, Klein was a strong contributor to the Redbirds' successful defense of the National League pennant. He appeared in 154 of the club's 157 official games, started 32 games at shortstop, and then succeeded Jimmy Brown as St. Louis' regular second baseman when Brown entered World War IImilitary service. Klein hit a career-high.287 and was second on the Cardinals in hits, runs scored and triples —behind only Stan Musial, an eventual Baseball Hall of Famer. During the 1943 World Series against the New York Yankees, he started all five games at second base but he collected only three hits, all singles, in 22 at bats and the Cardinals fell to the Yankees, four games to one. Klein then joined the United States Coast Guard, serving in Maryland and Florida, and missed all of and most of the season. When he returned to the Cardinals in September 1945, he battled for playing time on a talent-loaded team. Klein believed his future role in St. Louis would be limited as a utility player backing up the younger Red Schoendienst. Only two months into the 1946 season, with the Cardinals in first place, he jumped to the Mexican League, along with teammates Max Lanier and Fred Martin. Throughout the spring of 1946, the Pasquel brothers of the Mexican League had been making enticing offers to many low-paid Major Leaguers perpetually bound to their teams by the reserve clause. The trio of Cardinals were the latest group to accept. In an attempt to slow this exodus, Chandler banned all players who broke their existing contracts to join the Mexican League, including Klein, from organized baseball for a span of five years. On June 5, 1949, Chandler lifted the bans on the Mexican League jumpers, and eleven days later, Klein returned to the Cardinals. The Sporting News reported that he paid $1,500 out of his own pocket to buy his release from his independent club in the Quebec Provincial League to rejoin Organized Baseball.
Coach and manager
Klein's suspension-interrupted postwar MLB playing career was a far cry from his 1943 success. In 100 games for the Cardinals, and 51 more with the Indians and Athletics, he collected only 89 hits in 410 at bats and played full years in the minor leagues in 1950 and 1952–53. Altogether he batted.259 in 305 MLB games, his 269 hits including 45 doubles, 15 triples and 16 home runs. He had 101 runs batted in. Klein became a manager in the farm system of the Chicago Cubs in 1955. In 1960, he began the season as a coach for the MLB Cubs for half a season before swapping jobs with San Antonio Missions' manager Grady Hatton in midyear. Then, in, he was named to the infamous College of Coaches—a brainchild of owner Philip K. Wrigley, who decided to abolish the position of field manager and instead rotate "head coaches" to run the Cubs and their minor league affiliates. Klein was in charge of the Cubs for 11 games between September 1–10, 1961, and compiled a 5–6 win–loss record as head coach. He'd actually helmed clubs as low as Class D during the season. In 1962, Klein was named head coach again, replacing El Tappe and managing 30 games between May 1 and June 3. The 1962 Cubs finished 59–103 — their first time ever with a 100-loss season, and still the worst in franchise history. Only the 40–120 New York Mets were worse. In 1965, Klein was named to a third stint as head coach, replacing Bob Kennedy on June 14 and staying on through the rest of the season. The last head coach in the history of the College of Coaches, Klein went 48–58 in 1965, and finished with a lifetime 65–82 record. He remained in the Cub organization as a scout. Klein died in Metairie, Louisiana, at age 57 after suffering a stroke.
