McKain began playing professional baseball in 1930 with the
Pueblo Braves in the
Western League. In his second season, he compiled an 18–12 record for the Braves with a 3.86
earned run average (ERA). McKain advanced to AA baseball with the
Louisville Colonels of the American Association. His performance declined in 1931 as he compiled a 9–19 record. McKain remained with Louisville until 1935 when he joined the
Minneapolis Millers. He spent two-and-one-half seasons with the Tigers, compiling a 12–7 record and 3.74 ERA. McKain had his best season in 1940, compiling a 5–0 record with a 2.82 ERA (
adjusted ERA+ of 168) as the Tigers won the American League pennant. He appeared in game four of the
1940 World Series. In August 1941, the Tigers sold McKain to the
St. Louis Browns. He appeared in 18 games for the Browns in 1941 and 1943. When the Browns traded McKain to Brooklyn in July 1943, he retired from baseball. == Personal life ==