Mort Cooper signed at age 25 with the Cardinals and made his debut on September 14th, 1938. He made his last appearance with the Cubs on May 7, 1949.
In his first season he was 12-6 and on his way to a nice career. He hit his stride in 1942 when he was 22-7 and a 1.78 ERA along with 10 shutouts. Cooper was named National League MVP in 1942.
He followed that season with a 21-8 record and in 1944 was 22-7 with 7 shutouts. At the start of the 1945 season, both Mort and his brother Walker staged contract holdouts, demanding that the Cardinals raise their salaries to $15,000 each. Subsequently, Mort was traded that May to the Boston Braves after only three starts; bothered by longtime elbow problems, he ended the year only 9–4.
Cardinals career numbers
He was selected to the NL All-Star team four times (1942, 1943, 1945, 1946). His Cardinals record was 105-50 and a 2.77 ERA in 228 games. He started 186 games with 105 of the categorized as complete games.
Cooper tossed 28 shutouts for the Cardinals in 8 seasons and fanned 758 while walking 478 batters.