Babe Ruth did have some boxing connection. Ruth and Gehrig trained with boxing trainer Artie McGovern in the offseason. Ruth started after his awful 1925 season (and credited McGovern for getting him back into shape) and Gehrig was always into fitness and went to McGovern's too. I offer as proof of the latter:
McGovern signed this one:
Here's a fun article on Ruth's boxing training:
https://www.vice.com/en/article/8qyx...-great-bambino