Career
He made his Football League debut on 1 January 1939 against Blackpool. He played with Wolves until 1940 and the interruption of play in England due to World World War World War II During the 1939-1940 West Midlands (Regional) League play, McMahon had an impressive nine goals in six games for the Wolves "A" team, when league play was halted. During the war, McMahon served with Royal Canadian Naval Volunteer Reserves.
In England he guested for Chester, scoring six times against Stockport County in December 1939.
In 1946 McMahon played for the Chicago Vikings in the newly formed North American Soccer Football League. He played for Eastern Canada selects against the Eastern United States in 1947 and 1948 and then Scotland in 1949.