Mac Smith of the Hagerstown Packets collapses shortly after hitting a RBI single. He dies on the way to the hospital; doctors diagnose it as being due to malaria he had contracted while serving in the Korean War.

On July 2, 1954 Mac Smith of the Hagerstown Packets collapses shortly after hitting a RBI single. He dies on the way to the hospital; doctors diagnose it as being due to malaria he had contracted while serving in the Korean War.

 

Source:

Baseball Reference July 2