During a rain delay of a Richmond Roses-Marion Cubs game, Marion catcher Bob Osgood has a heart attack in the dugout. He dies at age 19. Osgood had a history of heart problems.

On May 11, 1948 — During a rain delay of a Richmond Roses-Marion Cubs game, Marion catcher Bob Osgood has a heart attack in the dugout. He dies at age 19. Osgood had a history of heart problems.

Source:
Baseball Reference May 11