He was an outfielder for the Cincinnati Reds (1940–43 and 1946), Boston Braves (1946–48), Brooklyn Dodgers (1949), New York Giants (1950), Chicago White Sox (1950) and Washington Senators (1951) of Major League Baseball.

McCormick was born in Angels Camp, California, stood 6 feet (180 cm) tall, weighed 190 pounds (86 kg), and threw and batted right-handed.

He helped the Reds win the 1940 World Series, and led the National League in sacrifice hits that season.

He served in the Army Air Force and played on a military baseball team with Joe DiMaggio in Hawaii.

The next year, he was signed by the New York Giants, played for Oakland of the Pacific Coast League, and had his contract purchased by the Chicago White Sox that June.