Prior to playing professional baseball, Kleinhans enlisted in the Ohio National Guard.

During World War I, the unit was mobilized and sent to France where he was wounded in the Meuse–Argonne offensive.

During World War II, he again served his country, this time as a captain with a US Army medical unit stationed in Scotland and England.

[1] From 1947 to 1966 Kleinhans was head coach for the Syracuse Orangemen baseball team, compiling a 156–146 (.516) record.

This biographical article relating to an American baseball pitcher born in the 1890s is a stub.