Cooper, whose brother Walker was his catcher during the early 1940s, went 22-7 with
10 shutouts and a 1.77 ERA and was the NL MVP for the 1942 World Champion Cardinals.
In 1943 he led the NL in victories (21) for the second straight year, and followed
with a 22-win 1944 campaign. The fastballer, who occasionally chewed aspirin on the
mound for relief from an aching arm, started and lost the 1942 and 1943 All-Star
Games. St. Louis traded Cooper to the Braves in May 1945 after suspending him for
leaving the club over a salary dispute. Mort and Walker teamed again in 1947, when
the fading pitcher appeared in eight games with the Giants.