Mort Cooper goes AWOL from the Cardinals, returning to St. Louis. A 20-game winner for three previous seasons, Cooper, along with his brother Walker Cooper, has had his salary frozen at $12,000 for three years, and is in a salary dispute with owner Sam Breadon. Without Cooper, the Cards drop a pair to the Braves, losing 5 – 4 in 14 innings and 4 – 1.

On May 16, 1945 — Mort Cooper goes AWOL from the Cardinals, returning to St. Louis. A 20-game winner for three previous seasons, Cooper, along with his brother Walker Cooper, has had his salary frozen at $12,000 for three years, and is in a salary dispute with owner Sam Breadon. Without Cooper, the Cards drop a pair to the Braves, losing 5 – 4 in 14 innings and 4 – 1.

Source:
Baseball Reference May 16