Slone grew up in New York City and attended Manhattan's High School of Commerce.

Slone signed with New York Hakoah of the ESL in 1928, beginning his twelve-year professional career.

I played professional soccer on the weekends, worked during the week and went to evening classes at St. John's University Law School.

This league lasted a season and a half before merging with the ASL at the end of the “Soccer War”.

Slone earned one cap with the U.S. national team in 1930 when he traveled to Uruguay for the 1930 FIFA World Cup.

At the time of his death, he was the last surviving member of the inaugural American World Cup team.